backup restention

[manilx]

I have a doubt about backup retention:

I have a backup like this:

8 bi-hourly and one last on the day w/healthcheck

Backup retention on those are keep 8 of the bihourly and 7 of the daily.
So this makes 9 per day, right?

If I Mirror delta backup to a remote storage, what is the retention to keep 1 week, 1 month?
9x7=63 for a week?
9x30=270 for a month?

I'm a bit confused.

[olivierlambert]

Adding @florent in the loop

edit: and @thomas-dkmt

[manilx]

@olivierlambert Great. Posted here and didn't open ticket because this is interesting for all ...