You can delete your BetterButter account and everything in it at any time, from the web or from the app. You do not need to contact us and nobody has to approve it.
Deleted immediately, not queued.
Any active subscription is cancelled as part of the same step, so you are not billed again. Call audio is never stored in the first place: it streams through for the conversation and is gone the moment the call ends, so there is no recording to delete.
Payment and cost records are retained where we are legally required to keep them for tax and accounting. Your user id is replaced with a pseudonym in those records, so they no longer identify you.
Full detail is in the privacy policy. Questions: support@betterbutter.app.