Updated documentation.

Author: jitran

README.md

@@ -128,7 +128,7 @@ For branch protection rules and rulesets, you can allow for status checks to be
 
 This can be defined at the org, sub-org, and repo level.
 
-To configure this for branch protection rules, specifiy `{{EXTERNALLY_DEFINED}}` under the `contexts` keyword:
+To configure this for branch protection rules, specify `{{EXTERNALLY_DEFINED}}` under the `contexts` keyword:
 ```yaml
 branches:
   - name: main

lib/plugins/overrides.js

@@ -21,8 +21,8 @@ module.exports = class Overrides extends ErrorStash {
   // When {{EXTERNALLY_DEFINED}} is found in the override value, retain the
   // existing value from GitHub.
   // Note:
-  //   - The admin settings could define multiple overrides, but the GitHub API
-  //     retains one only.
+  //   - The admin settings could define multiple status check rules for a
+  //     ruleset, but the GitHub API retains one only, i.e. the last one.
   //   - The PUT method for rulesets (update) allows for multiple overrides.
   //   - The POST method for rulesets (create) allows for one override only.
   static removeOverrides (overrides, source, existing) {