My machines didnt found anything for about 1 day ... usually it was getting around 3/day ...
today it didnt get anything

You should just look which of your servers run 1.031 version. Update these. It's a pretty good indicator that these have an older BLF file.
You do not need to look at the 1.067 Servers - if they get the block, they find it.
If you want a list of the 1.031 IPs I can send it via PM.
Rico