[Duplicity-talk] Full backups every second Saturday?

[Grant]

I'm running unattended backups and using --full-if-older-than 30D but
a lot of the time it uploads a full backup on a weekday which causes
the users sharing the network with my backup server to run into
bandwidth problems.  How best to do full backups something like every
second Saturday of the month?

I was thinking I could just run the first backup on a Saturday and do
--full-if-older-than 28D but then I'd have to remember to run the
first backup on a Saturday if I start over again at some point.

- Grant