At the end of November I read about a CZ.NIC project whose purpose is to verify the contact details of .CZ domain holders.
Since I have a MojeID account, the easiest way to verify the contact was via MojeID. I ran into a few obstacles. My registrar doesn't support MojeID. So I had to create an account with a new registrar that does support MojeID, then transfer the domain to their management and set everything up. It's somewhat surprising that Gransy — one of the leading registrars, under which station.cz also falls — doesn't support MojeID on that domain, but does support it on another of their domains. I received the validation confirmation by post together with a USB flash drive.