I think hosting the static dumps for owners that don't approve the auto-migration (and don't manually migrate) would be a great idea. Sure, you can't update you

I think hosting the static dumps for owners that don't approve the auto-migration (and don't manually migrate) would be a great idea. Sure, you can't update your site without migrating in the future, but you can always fix up the auto-migration after the fact. The important thing is that this would keep the old sites alive with a high fidelity.