@CuresedMushroom
I suspected that it was my router spooking around, I'm actually quite certain that's the issue.

Given that different servers use different ports, is there an easier way to bypassing port-forwarding than to do it for every server you want to play on?

I'm having the same issue, can't join any servers.

EDIT: I think I solved it by making an exception for DayZ in the windows firewall.
EDIT2: Maybe not...