Wow, that is extremely impressive!!! And guys come on the forum saying you need to run grams of gear or "aggressive" cycles to make gains. Love the shirt too, lol.
Probably shoulders. That is one of the reasons why I don't train them directly anymore. They get worked with so many exercises. Don't even worry about the diet for one day. Just switch it up tomorrow and all good! Another really solid update.
You have to focus on your diet and training into PCT or you are going to lose a lot. Running a good PCT that includes HCGenerate will help you feel better as you are recovering.