Patch 1.2's details note a fix to a problem involving the Wonder Trade feature - Pokemon that evolve due to being traded through Wonder Trade will now be capable of learning new moves. An issue where "certain captions" for Trainer PR videos weren't properly unlocking in Lumiose City has been addressed as well. The notes also list an update to an "internet communication issue," which Destructoid reports is related to curbing the use of unofficial tools called Battle Analyzer and Instacheck.
Pokemon Champions will need to download this update before they can return to proving their abilities against opponents in online battles. If you've neglected your collection of new friends since October, Patch 1.2 also includes a previous patch addressing a saving glitch in Lumiose City.