My mum was moved to a nursing home.
The litter type is changed frequently.
She does this during the night usually. If during the day, it's when no one is in the room.
It's downstairs. The litter boxes are in the enclosed patio.
The two male cats always use the boxes. There are 4 litter boxes.
Our female, 4 year old calico had recently begun to pee on the bottom of the stairs. Doesn't matter that the litter boxes are clean. No UTI or other illnesses.