In his forum post, he confirmed that the 1.3 update will affect only some of the existing weapons, while other changes will only apply to weapons that are coming right after the update. He did not ellaborate on what are the existing weapons that will be affected by the changes but I'm pretty sure that Ubi will announce something regarding that matter this week. You can check his official statement below:
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.
The 1.3 update will be launch this coming June 28th but, we expect more news coming before the update hits. Rest assured that we will keep you posted!
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