In a post on the Ubisoft forums, the developer stated that the upcoming 1.3 patch will only affect certain current weapons, and only a few future ones:
“In putting together patch notes, it’s become clear that there are specific changes coming to the weapons that will impact some existing weapons. Some of the changes will only apply to weapons dropped after the update. There will be more information about this on Thursday in the State of the Game but it might be worth holding on to those crafting materials for now. Just thought you should know.
This comes after an E3 where Ubisoft officially revealed the release date for its Underground DLC. No doubt Ubisoft is trying to make sure the game is as stable as possible before it releases it’s first major DLC.