>Looks like some temporary compressed index files from the current run
>should be there but are not.  ...
>
>Do you see similar behavior ?

As Joshua said, this is to be expected.  Amanda is creating those files
and removing them during the time GNU tar is also backing them up.

You *might* (haven't test this) be able to use an exclude pattern to
make GNU tar ignore those files:

  ./usr/local/var/amanda/idx/DailySet1/index/*.tmp

JJ