Apologies if this is in the incorrect place, but I have found a bug. According to your description:

(as far as I know, that's why comments are appreciated :)
Give you 2 blueprints for the same item

Had this happen on 2 Jan, 2016

https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=591610591

Received 3 blueprints for Rocket Propelled Grenade.

Do you need more information for troubleshooting like what other mods I'm using? Please let me know, would love to help.