Merge PR #4745: Update contributing doc

CONTRIBUTING.md

@@ -199,7 +199,10 @@ only pull requests targeted directly against master.
 - start on `master`
 - create the release candidate branch `rc/v*` (going forward known as **RC**) and ensure it's protected against pushing from anyone except the release manager/coordinator. **no PRs targeting this branch should be merged unless exceptional circumstances arise**
 - on the `RC` branch, use `clog` to prepare the `CHANGELOG.md` and kick off a large round of simulation testing (e.g. 400 seeds for 2k blocks).
-- if errors are found during the simulation testing, commit the fixes to `master` and create a new `RC` branch (making sure to increment the `rcN`)
+- if errors are found during the simulation testing or if any last minute changes
+need to be introduced, create a new `RC` branch (making sure to increment the `rcN`)
+based off of the current `RC` branch and commit any fixes or changes
+  - the above requires that any commits introduced must also be merged back into `master` 
 - after simulation has successfully completed, create the release branch (`release/vX.XX.X`) from the `RC` branch
 - merge the release branch to `master` to incorporate the `CHANGELOG.md` updates
 - delete the `RC` branches