My 40 yo former bodybuilder buddy had that done last May or June, thought it was just the 3 or 4 things in the rotator cuff but ended up also being a torn bicep.

He said he is a side sleeper and couldn’t really sleep in anything but a recliner for several months.  Bicep very painful.  He had the bionic arm freezer sling and said it helped.  Could not grab anything with his hand for several months.  He was making real rapid progress in PT and was well ahead of the expected curve in Oct (about 6mo) due to his former muscle tone then his PT got sick or something and he regressed.  Kind of stalled out at being able to lift his arm above his head with any weight bearing.  Drives all the time in a car and picks up whatever he wants underhand by his waist.  Now back into PT and going to continue.  

The torn bicep is the real deal.  Said it was originally expected to be 14 mo until fully rehabbed.