An update after eight months.
I am doing OK, continue to improve slowly.
All symptoms in arms (pain and numbness) went away, but still have a lot of achiness in neck and shoulders.
I think neck pain is mostly myofascial and exercises don't seem to do much for it.
Shoulders are diifferent. When I have pain (usually when I overdo it on the computer), it is more intense and disabling. I also have muscle atrophy in the trapezius which I suppose means nerve damage (although not all Drs agree - they can't agree on anything).
Anyway, I still do Edgelow's breathing exercises 3-4 times daily. I think other exercises of his are less helpful so I am gradually replacing them with strengthening exercises (crunches, prone cobras, bridges, weights etc).
I found strengthening to only helpful when the pain is gone. They were only making pain worse when I was in bad pain.

Even though I am feeling much better, I am clearly not ready to go back to work in the office full time
I usually only show up once a week or so for half a day.

Will keep you updated on the progress.