diff --git a/.github/workflows/abtesting.yml b/.github/workflows/abtesting.yml
index 32f410ac3c6..bd56f8190cc 100644
--- a/.github/workflows/abtesting.yml
+++ b/.github/workflows/abtesting.yml
@@ -24,11 +24,8 @@ jobs:
     strategy:
       matrix:
         include:
-          - os: macos-13
-            xcode: Xcode_15.2
-            target: ios
           - os: macos-14
-            xcode: Xcode_15.4
+            xcode: Xcode_16.2
             target: ios
           - os: macos-15
             xcode: Xcode_16.2
@@ -61,11 +58,13 @@ jobs:
   spm-package-resolved:
     env:
       FIREBASECI_USE_LATEST_GOOGLEAPPMEASUREMENT: 1
-    runs-on: macos-14
+    runs-on: macos-15
     outputs:
       cache_key: ${{ steps.generate_cache_key.outputs.cache_key }}
     steps:
       - uses: actions/checkout@v4
+      - name: Xcode
+        run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
       - name: Generate Swift Package.resolved
         id: swift_package_resolve
         run: |
@@ -88,11 +87,8 @@ jobs:
     strategy:
       matrix:
         include:
-          - os: macos-13
-            xcode: Xcode_15.2
-            target: iOS
           - os: macos-14
-            xcode: Xcode_15.4
+            xcode: Xcode_16.2
             target: iOS
           - os: macos-15
             xcode: Xcode_16.2
@@ -164,10 +160,12 @@ jobs:
     env:
       plist_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
       signin_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
-    runs-on: macos-14
+    runs-on: macos-15
     steps:
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Setup quickstart
       env:
         LEGACY: true
@@ -187,7 +185,7 @@ jobs:
     env:
       plist_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
       signin_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
-    runs-on: macos-14
+    runs-on: macos-15
     steps:
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
@@ -201,6 +199,8 @@ jobs:
     - name: Install Secret GoogleService-Info.plist
       run: scripts/decrypt_gha_secret.sh scripts/gha-encrypted/qs-abtesting.plist.gpg \
           quickstart-ios/abtesting/GoogleService-Info.plist "$plist_secret"
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Build swift quickstart
       env:
         LEGACY: true
@@ -216,7 +216,7 @@ jobs:
     # Don't run on private repo.
     if: github.event_name == 'schedule' && github.repository == 'Firebase/firebase-ios-sdk'
 
-    runs-on: macos-14
+    runs-on: macos-15
     strategy:
       matrix:
         target: [ios, tvos, macos]
@@ -229,6 +229,8 @@ jobs:
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
     - name: Setup Bundler
       run: scripts/setup_bundler.sh
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: PodLibLint ABTesting Cron
       run: |
         scripts/third_party/travis/retry.sh scripts/pod_lib_lint.rb \
diff --git a/.github/workflows/database.yml b/.github/workflows/database.yml
index 0e72e2c7c66..4f6ef256257 100644
--- a/.github/workflows/database.yml
+++ b/.github/workflows/database.yml
@@ -29,7 +29,7 @@ jobs:
         target: [ios, tvos, macos --skip-tests, watchos]
         build-env:
           - os: macos-14
-            xcode: Xcode_15.2
+            xcode: Xcode_16.2
           - os: macos-15
             xcode: Xcode_16.2
     runs-on: ${{ matrix.build-env.os }}
@@ -46,7 +46,7 @@ jobs:
   integration:
     # Don't run on private repo unless it is a PR.
     if: (github.repository == 'Firebase/firebase-ios-sdk' && github.event_name == 'schedule') || github.event_name == 'pull_request'
-    runs-on: macos-14
+    runs-on: macos-15
     steps:
     - uses: actions/checkout@v4
     - uses: mikehardy/buildcache-action@c87cea0ccd718971d6cc39e672c4f26815b6c126
@@ -58,7 +58,7 @@ jobs:
     - name: Install xcpretty
       run: gem install xcpretty
     - name: Xcode
-      run: sudo xcode-select -s /Applications/Xcode_15.2.app/Contents/Developer
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: IntegrationTest
       # Only iOS to mitigate flakes.
       run: scripts/third_party/travis/retry.sh scripts/build.sh Database iOS integration
@@ -71,6 +71,8 @@ jobs:
       cache_key: ${{ steps.generate_cache_key.outputs.cache_key }}
     steps:
       - uses: actions/checkout@v4
+      - name: Xcode
+        run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
       - name: Generate Swift Package.resolved
         id: swift_package_resolve
         run: |
@@ -93,11 +95,8 @@ jobs:
     strategy:
       matrix:
         include:
-          - os: macos-13
-            xcode: Xcode_15.2
-            target: iOS
           - os: macos-14
-            xcode: Xcode_15.4
+            xcode: Xcode_16.2
             target: iOS
           - os: macos-15
             xcode: Xcode_16.2
@@ -156,7 +155,7 @@ jobs:
     env:
       plist_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
       signin_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
-    runs-on: macos-14
+    runs-on: macos-15
     steps:
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
@@ -165,6 +164,8 @@ jobs:
     - name: Install Secret GoogleService-Info.plist
       run: scripts/decrypt_gha_secret.sh scripts/gha-encrypted/qs-database.plist.gpg \
           quickstart-ios/database/GoogleService-Info.plist "$plist_secret"
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Test objc quickstart
       run: ([ -z $plist_secret ] || scripts/third_party/travis/retry.sh scripts/test_quickstart.sh Database false)
     - name: Test swift quickstart
@@ -173,7 +174,7 @@ jobs:
   database-cron-only:
     # Don't run on private repo.
     if: github.event_name == 'schedule' && github.repository == 'Firebase/firebase-ios-sdk'
-    runs-on: macos-14
+    runs-on: macos-15
     strategy:
       matrix:
         podspec: [FirebaseDatabase.podspec]
@@ -185,6 +186,8 @@ jobs:
     steps:
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Setup Bundler
       run: scripts/setup_bundler.sh
     - name: PodLibLint database Cron
diff --git a/.github/workflows/dynamiclinks.yml b/.github/workflows/dynamiclinks.yml
index ff8fe073535..246b3799877 100644
--- a/.github/workflows/dynamiclinks.yml
+++ b/.github/workflows/dynamiclinks.yml
@@ -25,7 +25,7 @@ jobs:
       matrix:
         include:
           - os: macos-14
-            xcode: Xcode_15.2
+            xcode: Xcode_16.2
           - os: macos-15
             xcode: Xcode_16.2
     runs-on: ${{ matrix.os }}
@@ -47,6 +47,8 @@ jobs:
       cache_key: ${{ steps.generate_cache_key.outputs.cache_key }}
     steps:
       - uses: actions/checkout@v4
+      - name: Xcode
+        run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
       - name: Generate Swift Package.resolved
         id: swift_package_resolve
         run: |
@@ -69,10 +71,8 @@ jobs:
     strategy:
       matrix:
         include:
-          - os: macos-13
-            xcode: Xcode_15.2
           - os: macos-14
-            xcode: Xcode_15.4
+            xcode: Xcode_16.2
           - os: macos-15
             xcode: Xcode_16.2
     runs-on: ${{ matrix.os }}
@@ -93,7 +93,7 @@ jobs:
     # Don't run on private repo.
     if: github.event_name == 'schedule' && github.repository == 'Firebase/firebase-ios-sdk'
 
-    runs-on: macos-14
+    runs-on: macos-15
     strategy:
       matrix:
         flags: [
@@ -105,6 +105,8 @@ jobs:
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
     - name: Setup Bundler
       run: scripts/setup_bundler.sh
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: PodLibLint Storage Cron
       run: scripts/third_party/travis/retry.sh scripts/pod_lib_lint.rb FirebaseDynamicLinks.podspec --platforms=ios ${{ matrix.flags }}  --allow-warnings
 
@@ -119,6 +121,8 @@ jobs:
     steps:
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Setup quickstart
       run: scripts/setup_quickstart.sh DynamicLinks
     - name: Install Secret GoogleService-Info.plist
@@ -142,13 +146,15 @@ jobs:
     env:
       plist_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
       signin_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
-    runs-on: macos-14
+    runs-on: macos-15
     steps:
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
     - uses: actions/setup-python@v5
       with:
         python-version: '3.11'
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Setup quickstart
       run: scripts/setup_quickstart.sh DynamicLinks
     - name: Install Secret GoogleService-Info.plist
diff --git a/.github/workflows/firebase_app_check.yml b/.github/workflows/firebase_app_check.yml
index bb796e9ffc8..814a142b33b 100644
--- a/.github/workflows/firebase_app_check.yml
+++ b/.github/workflows/firebase_app_check.yml
@@ -25,7 +25,7 @@ jobs:
         target: [ios, tvos, macos --skip-tests, watchos]
         build-env:
           - os: macos-14
-            xcode: Xcode_15.2
+            xcode: Xcode_16.2
           - os: macos-15
             xcode: Xcode_16.2
     runs-on: ${{ matrix.build-env.os }}
@@ -58,7 +58,7 @@ jobs:
   diagnostics:
     # Don't run on private repo unless it is a PR.
     if: (github.repository == 'Firebase/firebase-ios-sdk' && github.event_name == 'schedule') || github.event_name == 'pull_request'
-    runs-on: macos-14
+    runs-on: macos-15
     strategy:
       matrix:
         diagnostic: [tsan, asan, ubsan]
@@ -67,6 +67,8 @@ jobs:
     - uses: mikehardy/buildcache-action@c87cea0ccd718971d6cc39e672c4f26815b6c126
       with:
         cache_key: ${{ matrix.diagnostics }}
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Initialize xcodebuild
       run: scripts/setup_spm_tests.sh
     - name: iOS Unit Tests
@@ -81,7 +83,7 @@ jobs:
   app_check-cron-only:
     # Don't run on private repo.
     if: github.event_name == 'schedule' && github.repository == 'Firebase/firebase-ios-sdk'
-    runs-on: macos-14
+    runs-on: macos-15
     strategy:
       matrix:
         flags: [
@@ -91,6 +93,8 @@ jobs:
     steps:
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Setup Bundler
       run: scripts/setup_bundler.sh
     - name: PodLibLint FirebaseAppCheck Cron
@@ -105,6 +109,8 @@ jobs:
       cache_key: ${{ steps.generate_cache_key.outputs.cache_key }}
     steps:
       - uses: actions/checkout@v4
+      - name: Xcode
+        run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
       - name: Generate Swift Package.resolved
         id: swift_package_resolve
         run: |
@@ -127,11 +133,8 @@ jobs:
     strategy:
       matrix:
         include:
-          - os: macos-13
-            xcode: Xcode_15.2
-            target: iOS
           - os: macos-14
-            xcode: Xcode_15.4
+            xcode: Xcode_16.2
             target: iOS
           - os: macos-15
             xcode: Xcode_16.2
diff --git a/.github/workflows/inappmessaging.yml b/.github/workflows/inappmessaging.yml
index 63a5624414f..d4786922a2f 100644
--- a/.github/workflows/inappmessaging.yml
+++ b/.github/workflows/inappmessaging.yml
@@ -27,7 +27,7 @@ jobs:
         podspec: [FirebaseInAppMessaging.podspec]
         build-env:
           - os: macos-14
-            xcode: Xcode_15.2
+            xcode: Xcode_16.2
           - os: macos-15
             xcode: Xcode_16.2
     runs-on: ${{ matrix.build-env.os }}
@@ -46,13 +46,13 @@ jobs:
     if: (github.repository == 'Firebase/firebase-ios-sdk' && github.event_name == 'schedule') || github.event_name == 'pull_request'
 
 # TODO(#12770): Update to macos-14 when tests are updated for Xcode 15.
-    runs-on: macos-13
+    runs-on: macos-15
     strategy:
       matrix:
 # TODO(#8682): Reenable iPad after fixing Xcode 13 test failures.
 #        platform: [iOS, iPad]
         platform: [iOS]
-        xcode: [Xcode_14.2]
+        xcode: [Xcode_16.2]
     steps:
     - uses: actions/checkout@v4
     - uses: mikehardy/buildcache-action@c87cea0ccd718971d6cc39e672c4f26815b6c126
@@ -76,6 +76,8 @@ jobs:
       cache_key: ${{ steps.generate_cache_key.outputs.cache_key }}
     steps:
       - uses: actions/checkout@v4
+      - name: Xcode
+        run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
       - name: Generate Swift Package.resolved
         id: swift_package_resolve
         run: |
@@ -98,10 +100,8 @@ jobs:
     strategy:
       matrix:
         include:
-          - os: macos-13
-            xcode: Xcode_15.2
           - os: macos-14
-            xcode: Xcode_15.4
+            xcode: Xcode_16.2
           - os: macos-15
             xcode: Xcode_16.2
     runs-on: ${{ matrix.os }}
@@ -122,7 +122,7 @@ jobs:
     # Don't run on private repo.
     if: github.event_name == 'schedule' && github.repository == 'Firebase/firebase-ios-sdk'
 
-    runs-on: macos-14
+    runs-on: macos-15
     strategy:
       matrix:
         flags: [
@@ -133,6 +133,8 @@ jobs:
     steps:
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Setup Bundler
       run: scripts/setup_bundler.sh
     - name: PodLibLint InAppMessaging Cron
@@ -151,6 +153,8 @@ jobs:
     - uses: actions/checkout@v4
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Setup quickstart
       run: scripts/setup_quickstart.sh inappmessaging
     - name: install secret googleservice-info.plist
diff --git a/.github/workflows/installations.yml b/.github/workflows/installations.yml
index 659c1958b87..0d3153e5dd2 100644
--- a/.github/workflows/installations.yml
+++ b/.github/workflows/installations.yml
@@ -28,7 +28,7 @@ jobs:
         target: [ios, tvos, macos --skip-tests, watchos]
         build-env:
           - os: macos-14
-            xcode: Xcode_15.2
+            xcode: Xcode_16.2
             test-specs: unit,integration
           - os: macos-15
             xcode: Xcode_16.2
@@ -65,6 +65,8 @@ jobs:
       cache_key: ${{ steps.generate_cache_key.outputs.cache_key }}
     steps:
       - uses: actions/checkout@v4
+      - name: Xcode
+        run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
       - name: Generate Swift Package.resolved
         id: swift_package_resolve
         run: |
@@ -86,11 +88,8 @@ jobs:
     strategy:
       matrix:
         include:
-          - os: macos-13
-            xcode: Xcode_15.2
-            target: iOS
           - os: macos-14
-            xcode: Xcode_15.4
+            xcode: Xcode_16.2
             target: iOS
           - os: macos-15
             xcode: Xcode_16.2
@@ -144,10 +143,12 @@ jobs:
     # Don't run on private repo unless it is a PR.
     if: (github.repository == 'Firebase/firebase-ios-sdk' && github.event_name == 'schedule') || github.event_name == 'pull_request'
 
-    runs-on: macos-14
+    runs-on: macos-15
     steps:
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Setup quickstart
       run: scripts/setup_quickstart.sh installations
     - name: Copy mock plist
@@ -161,13 +162,15 @@ jobs:
     # Don't run on private repo.
     if: github.repository == 'Firebase/firebase-ios-sdk' && github.event_name == 'schedule'
 
-    runs-on: macos-14
+    runs-on: macos-15
     steps:
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
     - uses: actions/setup-python@v5
       with:
         python-version: '3.11'
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Setup quickstart
       run: scripts/setup_quickstart.sh installations
     - name: Copy mock plist
@@ -186,7 +189,7 @@ jobs:
   installations-cron-only:
     if: github.event_name == 'schedule' && github.repository == 'Firebase/firebase-ios-sdk'
 
-    runs-on: macos-14
+    runs-on: macos-15
     env:
       plist_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
       FIR_IID_INTEGRATION_TESTS_REQUIRED: ${{ secrets.GHASecretsGPGPassphrase1 }}
@@ -200,6 +203,8 @@ jobs:
     steps:
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Setup Bundler
       run: scripts/setup_bundler.sh
     - name: Configure test keychain
diff --git a/.github/workflows/messaging.yml b/.github/workflows/messaging.yml
index a1caa67cb5d..a84b5e4d39a 100644
--- a/.github/workflows/messaging.yml
+++ b/.github/workflows/messaging.yml
@@ -30,7 +30,7 @@ jobs:
     if: (github.repository == 'Firebase/firebase-ios-sdk' && github.event_name == 'schedule') || github.event_name == 'pull_request'
     env:
       plist_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
-    runs-on: macos-14
+    runs-on: macos-15
     steps:
     - uses: actions/checkout@v4
     - uses: mikehardy/buildcache-action@c87cea0ccd718971d6cc39e672c4f26815b6c126
@@ -39,6 +39,8 @@ jobs:
     - name: Configure test keychain
       run: scripts/configure_test_keychain.sh
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Setup Bundler
       run: scripts/setup_bundler.sh
     - name: Install xcpretty
@@ -48,8 +50,6 @@ jobs:
         mkdir FirebaseMessaging/Tests/IntegrationTests/Resources
         scripts/decrypt_gha_secret.sh scripts/gha-encrypted/messaging-sample-plist.gpg \
           FirebaseMessaging/Tests/IntegrationTests/Resources/GoogleService-Info.plist "$plist_secret"
-    - name: Xcode
-      run: sudo xcode-select -s /Applications/Xcode_15.2.app/Contents/Developer
     - name: BuildAndTest
       run: ([ -z $plist_secret ] || scripts/third_party/travis/retry.sh scripts/build.sh Messaging all)
 
@@ -62,7 +62,7 @@ jobs:
         target: [ios, tvos, macos --skip-tests, watchos --skip-tests] # skipping tests on mac because of keychain access
         build-env:
           - os: macos-14
-            xcode: Xcode_15.3
+            xcode: Xcode_16.2
             tests: --test-specs=unit
           - os: macos-15
             xcode: Xcode_16.2
@@ -86,6 +86,8 @@ jobs:
       cache_key: ${{ steps.generate_cache_key.outputs.cache_key }}
     steps:
       - uses: actions/checkout@v4
+      - name: Xcode
+        run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
       - name: Generate Swift Package.resolved
         id: swift_package_resolve
         run: |
@@ -108,11 +110,8 @@ jobs:
     strategy:
       matrix:
         include:
-          - os: macos-13
-            xcode: Xcode_15.2
-            target: iOS spm
           - os: macos-14
-            xcode: Xcode_15.4
+            xcode: Xcode_16.2
             target: iOS spmbuildonly
           - os: macos-15
             xcode: Xcode_16.2
@@ -198,13 +197,15 @@ jobs:
     env:
       plist_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
       signin_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
-    runs-on: macos-14
+    runs-on: macos-15
     steps:
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
     - uses: actions/setup-python@v5
       with:
         python-version: '3.11'
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Setup quickstart
       run: scripts/setup_quickstart.sh messaging
     - name: Install Secret GoogleService-Info.plist
@@ -231,11 +232,11 @@ jobs:
         target: [ios, tvos, macos --skip-tests, watchos --skip-tests]
         os: [macos-14, macos-13]
         include:
-          - os: macos-14
-            xcode: Xcode_15.3
+          - os: macos-15
+            xcode: Xcode_16.2
             tests: --test-specs=unit
-          - os: macos-13
-            xcode: Xcode_15.2
+          - os: macos-14
+            xcode: Xcode_16.2
             tests: --skip-tests
     runs-on: ${{ matrix.os }}
     steps:
@@ -253,7 +254,7 @@ jobs:
     if: (github.repository == 'Firebase/firebase-ios-sdk' && github.event_name == 'schedule') || github.event_name == 'pull_request'
     env:
       plist_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
-    runs-on: macos-13
+    runs-on: macos-15
     steps:
     - uses: actions/checkout@v4
     - uses: mikehardy/buildcache-action@c87cea0ccd718971d6cc39e672c4f26815b6c126
@@ -269,7 +270,7 @@ jobs:
     - name: Prereqs
       run: scripts/install_prereqs.sh MessagingSample iOS
     - name: Xcode
-      run: sudo xcode-select -s /Applications/Xcode_15.2.app/Contents/Developer
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Build
       run: ([ -z $plist_secret ] || scripts/build.sh MessagingSample iOS)
 
@@ -278,7 +279,7 @@ jobs:
     if: (github.repository == 'Firebase/firebase-ios-sdk' && github.event_name == 'schedule') || github.event_name == 'pull_request'
     env:
       plist_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
-    runs-on: macos-13
+    runs-on: macos-15
     steps:
     - uses: actions/checkout@v4
     - uses: mikehardy/buildcache-action@c87cea0ccd718971d6cc39e672c4f26815b6c126
@@ -294,7 +295,7 @@ jobs:
     - name: Prereqs
       run: scripts/install_prereqs.sh SwiftUISample iOS
     - name: Xcode
-      run: sudo xcode-select -s /Applications/Xcode_15.2.app/Contents/Developer
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Build
       run: ([ -z $plist_secret ] || scripts/build.sh SwiftUISample iOS)
 
@@ -303,7 +304,7 @@ jobs:
     if: (github.repository == 'Firebase/firebase-ios-sdk' && github.event_name == 'schedule') || github.event_name == 'pull_request'
     env:
       plist_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
-    runs-on: macos-13
+    runs-on: macos-15
     steps:
     - uses: actions/checkout@v4
     - uses: mikehardy/buildcache-action@c87cea0ccd718971d6cc39e672c4f26815b6c126
@@ -319,7 +320,7 @@ jobs:
     - name: Prereqs
       run: scripts/install_prereqs.sh MessagingSampleStandaloneWatchApp watchOS
     - name: Xcode
-      run: sudo xcode-select -s /Applications/Xcode_15.2.app/Contents/Developer
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Build
       run: ([ -z $plist_secret ] || scripts/build.sh MessagingSampleStandaloneWatchApp watchOS)
 
diff --git a/.github/workflows/remoteconfig.yml b/.github/workflows/remoteconfig.yml
index 42f00785b91..c6ca84bbd1b 100644
--- a/.github/workflows/remoteconfig.yml
+++ b/.github/workflows/remoteconfig.yml
@@ -26,7 +26,7 @@ jobs:
     env:
       plist_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
       USE_REAL_CONSOLE: true
-    runs-on: macos-14
+    runs-on: macos-15
     strategy:
       matrix:
         target: [iOS]
@@ -47,6 +47,8 @@ jobs:
       if: matrix.target == 'iOS'
       run: ([ -z $plist_secret ] || scripts/generate_access_token.sh "$plist_secret" scripts/gha-encrypted/RemoteConfigSwiftAPI/ServiceAccount.json.gpg
           FirebaseRemoteConfig/Tests/Swift/AccessToken.json)
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Fake Console API Tests
       run: scripts/third_party/travis/retry.sh scripts/build.sh RemoteConfig ${{ matrix.target }} fakeconsole
     - name: IntegrationTest
@@ -65,9 +67,9 @@ jobs:
         podspec: [FirebaseRemoteConfig.podspec]
         build-env:
           - os: macos-14
-            xcode: Xcode_15.3
-            # TODO(#13078): Fix testing infra to enforce warnings again.
-            tests: --allow-warnings
+            xcode: Xcode_16.2
+#            # TODO(#13078): Fix testing infra to enforce warnings again.
+#            tests: --allow-warnings
           # Flaky tests on CI
           - os: macos-15
             xcode: Xcode_16.2
@@ -93,6 +95,8 @@ jobs:
       cache_key: ${{ steps.generate_cache_key.outputs.cache_key }}
     steps:
       - uses: actions/checkout@v4
+      - name: Xcode
+        run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
       - name: Generate Swift Package.resolved
         id: swift_package_resolve
         run: |
@@ -115,12 +119,8 @@ jobs:
     strategy:
       matrix:
         include:
-          - os: macos-13
-            xcode: Xcode_15.2
-            target: iOS
-            test: spm
           - os: macos-14
-            xcode: Xcode_15.4
+            xcode: Xcode_16.2
             target: iOS
             test: spm
           - os: macos-15
@@ -193,6 +193,8 @@ jobs:
     steps:
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Setup quickstart
       run: scripts/setup_quickstart.sh config
     - name: Install Secret GoogleService-Info.plist
@@ -232,7 +234,7 @@ jobs:
   sample-build-test:
     # Don't run on private repo unless it is a PR.
     if: (github.repository == 'Firebase/firebase-ios-sdk' && github.event_name == 'schedule') || github.event_name == 'pull_request'
-    runs-on: macos-14
+    runs-on: macos-15
     steps:
     - uses: actions/checkout@v4
     - uses: mikehardy/buildcache-action@c87cea0ccd718971d6cc39e672c4f26815b6c126
@@ -242,7 +244,7 @@ jobs:
     - name: Setup Bundler
       run: scripts/setup_bundler.sh
     - name: Xcode
-      run: sudo xcode-select -s /Applications/Xcode_15.4.app/Contents/Developer
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Prereqs
       run: scripts/install_prereqs.sh RemoteConfigSample iOS
     - name: Build
@@ -251,7 +253,7 @@ jobs:
   remoteconfig-cron-only:
     # Don't run on private repo.
     if: github.event_name == 'schedule' && github.repository == 'Firebase/firebase-ios-sdk'
-    runs-on: macos-14
+    runs-on: macos-15
     strategy:
       matrix:
         target: [ios, tvos, macos]
@@ -262,6 +264,8 @@ jobs:
     steps:
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@354a1ad156761f5ee2b7b13fa8e09943a5e8d252 # v1
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
     - name: Setup Bundler
       run: scripts/setup_bundler.sh
     - name: PodLibLint RemoteConfig Cron
diff --git a/.github/workflows/shared-swift.yml b/.github/workflows/shared-swift.yml
index 1da058f15ca..4975512fcf2 100644
--- a/.github/workflows/shared-swift.yml
+++ b/.github/workflows/shared-swift.yml
@@ -27,7 +27,7 @@ jobs:
         target: [ios, tvos, macos, watchos]
         build-env:
           - os: macos-14
-            xcode: Xcode_15.2
+            xcode: Xcode_16.2
             swift_version: 5.9
           - os: macos-15
             xcode: Xcode_16.2
@@ -56,6 +56,8 @@ jobs:
       cache_key: ${{ steps.generate_cache_key.outputs.cache_key }}
     steps:
       - uses: actions/checkout@v4
+      - name: Xcode
+        run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
       - name: Generate Swift Package.resolved
         id: swift_package_resolve
         run: |
@@ -80,7 +82,7 @@ jobs:
         target: [iOS, tvOS, macOS, catalyst, watchOS]
         build-env:
           - os: macos-14
-            xcode: Xcode_15.2
+            xcode: Xcode_16.2
           - os: macos-15
             xcode: Xcode_16.2
     runs-on: ${{ matrix.build-env.os }}
diff --git a/scripts/build.sh b/scripts/build.sh
index d5776e4e3c1..da430d12a19 100755
--- a/scripts/build.sh
+++ b/scripts/build.sh
@@ -440,7 +440,7 @@ case "$product-$platform-$method" in
       RunXcodebuild \
         -workspace 'FirebaseMessaging/Apps/SampleStandaloneWatchApp/SampleStandaloneWatchApp.xcworkspace' \
         -scheme "SampleStandaloneWatchApp Watch App" \
-        -destination 'platform=watchOS Simulator,name=Apple Watch Series 7 (45mm)' \
+        -destination 'platform=watchOS Simulator,name=Apple Watch Series 10 (42mm)' \
         build
     fi
     ;;