Thanks to all for your suggestions. I understand that these are opinions with no guarantees.
I'm certainly not aware of any of those mysterious 'unusual circumstances' regarding my exam, diagnosis and so on. I was upfront and honest with the doctors questions, but I didn't sugarcoat my life, either. I believe that the rating was for very low social interaction. I go to work and often stay late because there's nothing going on at home to leave for. The work schedule provides structure for my day. At home, I live alone. I'm divorced and kids are off on their own about three hours away. I do have a lady-friend and we get together about once a week. In a couple of sentences - that's my life.
I have been going to a veterans group for many years and had tried some individual counseling, but no individual sessions recently. I suppose that I knew for a long time that I had PTSD. Two veteran counselors had told me that I had PTSD as an informal diagnosis. Recently I was talking to a Service Officer about claim for diabetes. She encouraged me to also submit a claim for PTSD. I did and it moved through the VA process very quickly.
Independent of the VA and disability stuff, I had been thinking that I would retire some time in the next two or three years. I'm sure that the financial side will work. My needs are not all that big and I have Social Security, a small pension and some savings. I had not planned on VA disability compensation in my retirement financial planning, beyond the 20% disability that I have had since about 1990. I'm still adjusting to the idea of this new rating.
As cooter suggested, it had also occurred to me that maybe this is the time. My thinking now is somewhere between seven and twenty months. Because of outside stuff and a situation at work, I wouldn't want to let people down by leaving before seven months. After that, I could go with a clear conscience. Beyond that, it's 20 months or LESS.
Just noting - RVN is Republic of Viet Nam.
Thanks to all for your input and suggestions.