Re-adds known issues to 8.16.2 and 8.16.3 release notes (#6440)

Author: nastasha-solomon

docs/release-notes/8.16.asciidoc

@@ -5,6 +5,30 @@
 [[release-notes-8.16.3]]
 === 8.16.3
 
+[discrete]
+[[known-issue-8.16.3]]
+==== Known issues
+
+// tag::known-issue[]
+[discrete]
+.Duplicate alerts can be produced from manually running threshold rules 
+[%collapsible]
+====
+*Details* +
+On November 12, 2024, it was discovered that manually running threshold rules could produce duplicate alerts if the date range was already covered by a scheduled rule execution.
+====
+// end::known-issue[]
+
+// tag::known-issue[]
+[discrete]
+.Manually running custom query rules with suppression could suppress more alerts than expected
+[%collapsible]
+====
+*Details* +
+On November 12, 2024, it was discovered that manually running a custom query rule with suppression could incorrectly inflate the number of suppressed alerts. 
+====
+// end::known-issue[]
+
 [discrete]
 [[bug-fixes-8.16.3]]
 ==== Bug fixes
@@ -29,6 +53,30 @@ Affected users who are unable to upgrade should set one or both of the following
 [[release-notes-8.16.2]]
 === 8.16.2
 
+[discrete]
+[[known-issue-8.16.2]]
+==== Known issues
+
+// tag::known-issue[]
+[discrete]
+.Duplicate alerts can be produced from manually running threshold rules 
+[%collapsible]
+====
+*Details* +
+On November 12, 2024, it was discovered that manually running threshold rules could produce duplicate alerts if the date range was already covered by a scheduled rule execution.
+====
+// end::known-issue[]
+
+// tag::known-issue[]
+[discrete]
+.Manually running custom query rules with suppression could suppress more alerts than expected
+[%collapsible]
+====
+*Details* +
+On November 12, 2024, it was discovered that manually running a custom query rule with suppression could incorrectly inflate the number of suppressed alerts. 
+====
+// end::known-issue[]
+
 [discrete]
 [[bug-fixes-8.16.2]]
 ==== Bug fixes