Share and share alike
Both Guinevere and Sinatra now occupy the same two rooms together. There is no hissing, growling or swatting, they lay side by side now. There is even a bit of mutual grooming going on and Sinatra seems quite protective of her.
I have been going up in the evenings and leaving the doors open and just sitting on the floor and reading out loud. Soon Sinatra will come into the room and he would lay down near my feet. Guinevere is usually on my lap by that point. I just keep reading and hope that my knees won’t turn into shredded meat if there is a confrontation.
I haven’t quite gotten to the point where I leave those doors open at night. Night is when cats become predator, and I would hate for the two of them with Sinatra in high prey mode to clash. So the doors stay open during the day only and at night each cat is retired into their respective rooms.