@Matthew791 No, it is not something you have to accept. You made a booking and the host can't simply decide to change the terms of that contract arbitrarily. If the host is willing to pay in full for a hotel room for the last night, and that works for you, I'd go for it, but otherwise, I'd tell the host that the change isn't acceptable and you don't agree to it, and if they aren't accomodating, contact Airbnb, who will contact the host to let them know they can't do this.
Kep all communiction with the host on the Airbnb messaging system.