Mom has day/night confusion

M1 is right, her confusion is global. She is not in control of her faculties. She should no longer be living alone. She likely has anosognosia, meaning she is unaware of having dementia or that she is in danger. You cannot convince her of reality, nor reason with her, nor teach her, nor expect her to use clocks or other devices or technology. The only thing to do is to take steps to ensure her safety. This may involve subterfuge. Read about anosognosia and learn the work-arounds that the members use. Read a lot of threads.

Iris

Yup, it's your warning shot off the bow that she can't live alone anymore she needs 24/7 supervision. Confusing days and nights will not be the only issue now, there are severe safety risks now for fires, wandering, being scammed or preyed upon, cooking, finances, all kinds of things. They all come together now in this not so fun phase. Her brain can't register logic so fancy clocks or tech won't help. We used a white board for a while with the date, season/weather, appointments etc and it helped a tiny bit, but only because mom was never alone and we discussed it together constantly. There is no substitute for 24/7 supervision either with family and hired staff in the home or a memory care facility. Once she is settled in a safe environment you could look at meds for the night disruptions. Many PWD benefit from a sleep med. Sometimes the antipsychotics prescribed for agitation have the added benefit of helping sleep, others folks just need something lighter. My mother took Remeron for sleep and it had the added benefit of being somewhat of an anti-depressive to help mood. It made our nights much more manageable.