Xavier.
Your host is killing your backup. They are killing the CRON job itself after X number of seconds. It is pretty common. If they won't extend the time limit, you just can't start the backup that way.
You can switch to a front end backup (you need to enable the backup and add a key under Options). You can see the format under Schedule Automatic Backups. Instructions for WebCron are given, this is a commercial service, but very inexpensive. This is not the only service but one that we're familiar with. You can trigger the backup from any computer that is powered on at the time you want your backup to run. Use Scheduled Tasks on Windows, CRON on Linux, you can even use a Raspberry Pi.
Dale L. Brackin
Support Specialist
English: native
Please keep in mind my timezone and cultural differences when reading my replies. Thank you!
????
My time zone is
EST (UTC -5) (click here to see my current time in Philadelphia, PA)