You would expect that, damage limitation. If rolling out a fix you would want to roll it out to your smallest customers first to verify then incrementally roll it out to more/larger customers as your confidence increases. Especially if it’s anything data/db migration related as some comments hint at and the mention of possible data loss being minimum in one of their official responses suggesting something data related.
On the status updates I guess they can’t say more other than they are working on it. Saying more at this time might open them up to other issues considering a lot of businesses are run off moving Jira tickets around today.