Hello!
At this stage we can say that the cause of this specific problem was essentially a ban against IP addresses, a ban which extended on all of our infrastructure to defend Air against attacks. To be banned an IP address has to fail several login attempts in a row in a short time.
As the whole matter involved at least 40 persons, probably some more, who did not change IP address in the last days, we can't say how it's possible that their IP addresses were all banned. We are searching for flaws in our anti-flood system. It is the same system that has been working fine with no modifications in the last 18-20 months so if there's some bug it's really well hidden and comes out so rarely. Even if it's a bug, why it did not affect, say 1000, 5000 or 20000 or ALL users, but just a tiny tiny fraction?
While a few cases might be explained by infected machines, when the owner is not even aware that the system performs attacks, we can't realistically assume that all of a sudden the machines of more than 40 users were infected all in the last 2-3 days, and all infected with the same peculiar malware which attacked AirVPN (too or exclusively).
We will keep you posted if we find anything relevant. In the meantime please keep reporting whether everything is fine or the problem comes back.
Kind regards