the home has warned they may not be able to keep my mum if her aggression doesn't settle

They have said they want to give her a proper chance to settle, but they are monitoring her closely and if nothing improves they may not be able to keep her. I feel completely out of my depth. Her dementia has moved much faster than I expected and I am still catching up. Has anyone been through this? What actually happens if a home gives notice, how much time do you get, and what sort of placement would even take her at that point?