Currently, if you have a CI job set up to validate based on events (push, pull request) on a specific branch the following occurs:

You open a pull request against the specific branch noted in the job - CI validation runs
You push a commit to the source branch of the same open PR - CI validation runs
You push a commit to the target branch of the same open PR - no validation runs

In the conversation with Dan on 8/13/2020, I was told this is by design on Gearset's end (to ignore that situation) to avoid long queued validations. While I agree with that decision, it'd be great to at least have the option to choose this behavior (whether to run or not) as a setting while creating the CI job.