Excellent question! Terra will automatically attempt to resend the event to your webhook after a period of 5 minutes, then 30 minutes, 1 hour, 2 hours, 4 hours and on and on. After 1 day, we stop retrying to send the same payload - this should give you ample time to fix your webhook when on production. You will always have the ability to resend any event that you can find on the debug log, by opening the event details panel (by pressing the > icon) and hitting Resend*. Also, the Terra api will always resend the payload to your currently configured hook - not an older webhook url.