Check out the Joint Policy Committee's latest Bulletin: "Joint Clarification on Downgrades and the Use of Material in New Commercials." The Bulletin provides helpful examples to clarify how the integration provisions (Section 25 of the SAG-AFTRA Commercial Contract) work when an actor who was engaged as an on-camera principal performer is later downgraded. This Bulletin is consistent with prior Bulletins, but provides a helpful reminder.
I hear the "hard copy" SAG-AFTRA Commercial Contracts will be available very soon - for those of us still living in the brick and mortar world.