Our process is to link Github PRs to cards before assigning them to a reviewer. PRs usefully show the status of checks, but when CI (Github "Checks") succeeds the status is incorrectly shown as a red "x", indicating failure. I think what might be happening is that Trello is reporting the "mergability" of the PR, which is negative before an approving review. This isn't very useful, I'd prefer Trello to show the "Checks" status and disregard the review status, or show that separately.
