Your cervix should return to it's "non fertile" state within 2 weeks of ovulation... which is Low, Firm & Closed.
I'm with you on the whole Open Closed thing... I always have trouble telling what's what with that.

I've taken to just not even putting in on my chart, I just mark height and texture and leave the open closed thing alone. LOL!
Do you normally spot prior to AF? Things could be a bit

due to this being your first cycle after your IUD removal. The fact that it's firm... sounds like it's doing what it's supposed to, it may drop to a lower position over the next day or so.