> Once you have blocks on the chain greater than 1mb, those blocks must be valid forever. That means protocol must support new blocksize forever. You could hav

> Once you have blocks on the chain greater than 1mb, those blocks must be valid forever. That means protocol must support new blocksize forever. You could have the consensus rules take the block height into consideration, so blocks after a certain # must be under X MB, but previous blocks can be up to Y MB.