Currently, we skip certain compatibility checks if the field is unstable. We skip the checks by only checking if the old version of the field is unstable. This is normally correct because we don't allow changing the field from stable in the old version to unstable in the new version. However, we now have some special cases in IGNORE_UNSTABLE_LIST where the field has changed from stable to unstable. We should change the script so that wherever we skip the compatibility checks if the old field is unstable, we also skip it if the field is in IGNORE_UNSTABLE_LIST