Based on my own experience operating websites… my guess is that they keep track of browser strings, IP addresses, and login times - and have some kind of offline job that can study all the same accounts that use the same IP addresses around similar times.
I suspect when when the admin looks at an account they can see information about your IP address history, geolocations, browsers, and detected secondary accounts.
How do they determine you evaded anyway?
Based on my own experience operating websites… my guess is that they keep track of browser strings, IP addresses, and login times - and have some kind of offline job that can study all the same accounts that use the same IP addresses around similar times.
I suspect when when the admin looks at an account they can see information about your IP address history, geolocations, browsers, and detected secondary accounts.