Is each retry delay counted from the initial failure?
Short answer
No. Each delay counts from the previous attempt. A policy with attempt 1 at plus 1 day and attempt 2 at plus 3 days retries on day 1 and day 4 after the failure, not on day 3. Delays can be set in minutes, hours, days or weeks, and the preview shows the resulting timeline.
In detail
No.
Delays chain
Each attempt is planned from the one before it, down to the minute.
Any unit
Minutes, hours, days or weeks, attempt by attempt.
The schedule stays put
Retries never move the billing date: the next rebill stays on its own date.