This seems totally possible to me. He may be just "saving" his arm and trying to give it more time to rehab it back to 100%. No sense "letting it loose" if the opportunity doesn't present itself. It said the Jays were working him back to 180 foot throws, but it never said he has to be able to throw 100% and hit his peak OF velo to return. It's a possibility they let him comeback earlier, knowing he wouldn't have this peak velo (yet), but that he also no longer has to worry about re-injuring it (more than normal).