i think the original leon map had this issue... at least on some as its seems common. once you remap it gets more noticable...its almost as if its holding power back under certain conditions except that cant be right as a restart solves it?
interesting what p-torque say about mapping around it.
320bhp is murdering your wallet time. bigger turbo,fpr,injectors, fmic ect ect...
if your thinking of going this way replace your fpr but keep it for the future..