I just meant I run a cron job daily to collect one days' worth of the debug files into a dated directory and remove any dated directory older than 30 days. That is not a builtin amanda facility. Something similar 'might' be doing nasty things to your index files.
Are they the most recent?
Yes.
Do they change daily?
Yes.
I do have a cron job that occasionally clears /tmp but much more infrequent than every three days. However, this machine does other housekeeping activities so it may be that I configured another script or program to clear out things. I'll keep an eye on that from now, it seems that this is the most likely reason.
/per olof