yast backup strange result (11.4)

Hello,
I have a hosted server (so no physical access) online. I back it up with yast. I have three different yast backup scripts (for the system, /home and /data).

This fits quite my needs. I have mostly to save the necessary time to upload again the data, will it be lost, because I have also local backups.

I receive daily reports.

The system report is curious. It’s reported size vary (around 1.7Gb, btween 1.6 and 1.8). I only backup what is not included in the standard package (anyway in case my computer break, I will get a new one installed). May be this show the automatic update work?

But the most curious is that this size do not reflect the actual size of the archive, that is more around 2.1Gb.

A good yast feature is that one can keep old backups files and choose how many, yast keep them with the date in they name.

Yesterday, I had to change part of the crontab (with crontab -e).

Today I had two yast reports, the second, 5 minutes after the first (2 in the morning) being:

/data/backup/automatique.tar -> /data/backup/19700101010000-automatique.tar
/data/backup/automatique.xml -> /data/backup/19700101010000-automatique.xml

notice the date. no such file on the system

any idea?
thanks
jdd