[mrkeen]

It would be outside of the normal exceptional cases, yes.

Like buggy data that crashes the system.

If you have the old events there, you can "measure twice, cut once", in the sense that you can keep re-running your old events and compare them to the new events under unit-test conditions, and be absolutely sure that your history re-writing won't break anything else.

It's not for just doing a refund or something.