If I was to workout for 8 weeks then rest for 2, should I keep my diet the same throughout, or would all that protein go to waste during the rest period (especially in the 2nd week)?
Eating lots of protein would help you keep muscle mass better than if you didn’t eat lots of it. If it’s only for two weeks I’d keep it the same, and maybe drop kcals a bit if your looking to not gain weight.