There are a number of Azeri and Georgian airlines, mostly flying 747s that fly between Baku and known military transit points and bases often several times a day. From Baku the same companies' smaller IL76s fly into the Gulf, Iraq and even Africa.
It doesn't take much to connect those dots.
But we've never seen Linz appear in this odd distribution chain. Linz Airport is actually a military airport but with a civil right of use.