My seat in N1E has changed from 341 to 126..... not sure how that translates to bunching seats up in North stand?
Good God! l could believe that it may have gone up a little bit to accomodate a few extra seats, but not by 476!
I don't know what part of the ground your seat is in, but mine in West Lower, (W1G), has kept the same number.
I think all stands have been renumbered starting at 1, rather than starting at 1 in the West Stand.