Thanks for the fast reply. I'm using one of the largest ISPs in Russia and they usually are good at monitoring and blocking that sort of thing but of course it still happens (until they block it).

Is there any way I can see/get the range of currently blocked addresses so I can check if that is the problem? (maybe a PM?) Does FT maintain their own list or they use a third-party blacklist?

If FT has their own list, for how long do the addresses stay blocked?