Unfortunately I wouldn't expect the next patch much before the add-on is out (August/September). With additional changes being made to the game, it doesn't really make sense to release multiple patches when a great deal of time and effort can be saved by combining the testing and release procedures for the patch and add-on. In particular, Microsoft has limits on the size and number of patches that can be released for Xbox games, though I would think the various publishers for the PC versions would also want to avoid too much duplication.

Though slightly less convenient, this problem can be avoided (if it occurs on the system in question) by not over-writing saves, and not using the quicksave function.