looking to migrate all our mainnet creator tokens onto an L2 ahead of a big feature launch
need to also migrate people's holdings, whats the best way to do this?

You take a snapshot of all the accounts holding the token, announce the plan, update the contracts, and airdrop then enforce by convention that the new tokens dropped and the old ones are now deprecated. You could also have some kind of mint-burn setup if you want the users to bridge it themselves.

Im the guy that posted all those factory memes once

Re: Update the contracts, you would redeploy your token contract on the L2. If you used create2 you should be to get the same address on the L2 as on L1 and it should be bridgeable via the canonical bridge for that L2