Comment # 1 on bug 1173723 from Coly Li

Can I know which mdadm version or openSUSE Leap version for "was once per
month" ?

Current upstream mdadm code has the following OnCalendar string:
 11 [Timer]
 12 OnCalendar=Sun *-*-1..7 1:00:00

It means weekly on every Sunday 1:00 am, it is defined a such way since first
time it was merged in.

Unfortunately the OnCalendar timer format was mistaken, the correct for-weekly
format should be,
 11 [Timer]
 12 OnCalendar=Sun *-*-* 1:00:00

This is what bug 1173137 fixed.

Coly Li