If a webhook request does not receive a success (2xx) response, it will be retried according to the following schedule, trying at most 10 times before giving up:

seconds_until_next_attempt = (2^(num_attempts_so_far) - 1) * 10

So, if the first attempt fails, the second will be scheduled to try again in (2^1 - 1) * 10 = 10 seconds.

Note that the delay between attempts is a minimum delay.