Is this a new stage of ALZ?

My husband has times that he is not his normal “abnormal” and it’s usually a UTI. Yesterday he was strangely cognitive. It wasn’t like when he has a UTI. We have lived with my girlfriend for almost two years and he (quietly, because he didn’t want her to hear us) just started asking questions about who owned what in the house. I told him the three of us own the house and he said I would have never agreeded to that. I assured him he did and that it was working out very well. This went on for a while. When I went in the help him get into bed that night he refused and I eventually left him in his chair. He has not been able to get the hang of the lift chair and often times he reclines it and then tries to get up without declining it. Last night when I went in one last time he had worked the chair correctly and got himself into bed. This morning I went in to help him change his diaper and he had removed the soiled one and put shorts on and put a folded diaper in his shorts over his personals. I tried to explain to him that the diaper wouldn’t work like that, and he went on to very reasonably explain why he did it. I helped him shower and dress, and after he had breakfast he went on to ask about some construction I had being done in the guest room. He also told me he had no way to get me a mother’s day gift. I told him that was fine...he went on about it, and I told him he has not gotten me a gift for any holiday in years and I was okay with that. He asked, “I get you birthday presents?” I said, “You have not remembered my birthday in several years and that’s fine.” While ALZ is still obvious, what is going on with his sudden cognitive reality? It’s not a bad thing, just so strange. He is 90 and we stopped his ALZ meds last year for several reasons and his behavior really had no noticeable changes. This illness is so baffling.