Yes, it is but its also possible to get it frozen for suspicious-ness and other reasons.
I still have some accs I gained access to a while ago, BUT some of the original owners been trying to get the accs back but failed.
I think they gave up, idk. Hopefully they gave up by now and stopped sending tickets because they wont be getting their accounts back.
If they never let their emails become unreg, then they wouldn't of lost their accounts.