And you're getting it many times? Both of them many times, daily? Or, just one?
You could remove the scripts from the rsyslog and put them as crontabs around 530am. Rsyslog rotates around 6am I think, check timestamps in your log dir for gz's and stuff.
If the cronjob only sends it once, then at least it's narrowed down to rsyslog or a multiple mail.log entry elsewhere causing a loop or something.
If cronjob sends it multiple times, there's an error in the script..
ISPC3 on Debian! It's great!