I noticed as I was upgrading my boat that I was able to build the Elite upgrades without first acquiring the plans. The requirement is written in red and crossed out, but for some reason I can still buy those upgrades. I chose not to until I actually found the plans, because I don't want to have them early. Why? I don't know, too honest maybe. Sadly I haven't found any elite plans except for mortar storage, and I'm getting upset. They must all be in the final area you can't go in until a later sequence. I'm experiencing this glitch on the Xbox One. Not sure if it's the same for other systems, but for sure on the One. I bet you never thought you'd see a complaint about a glitch that benefits the player, allowing us early access to later game items. Just wanted to make Ubisoft aware of the issue. I should probably go do those upgrades before the game is patched.