I guess it all depends on what is your actual goal? Do you want to play 4.5 or do you really want to go back to 4.0.
If you want to play 4.5, let your shoulder heal. If it is just rotator cuff tedonitis it will heal with rest and treatment. Just put off competitive playing until you are healed.
If you really want to get back to 4.0. Go out play some matches- lose them by wide margins. When ESR or end of year ratings come, you will be down to your old level.
It is highly doubtful that you will get a medical appeal. I know people with much worse conditions than yours that required surgery and they were out for 6-12 months and they were still denied.