I have been rated for sleep apnea, right shoulder (chronic torn labrum), migraines, and a few other conditions for 10 years now. I have a total rating of 90%, and have filed an increase which may put me at 100%. Given the length of time for my initial ratings, with no improvements, what are the chances of getting P&T? Thank you!
This is a tough one that I get a lot. First up...without knowing precisely what your ratings are today and exactly what you've done to file for an increase, I'm just guessing here.
The length of time your current ratings are in place won't have any effect on an increase to 100%. What will have an impact is VA Math. VA Math is where 2 + 2 doesn't equal 4.
To increase from 90% to 100% is often impossible due to the Combined Ratings Table. It's an awkward device to use and if you do a search you'll find all sorts of calculators that purport to help (and don't) so I think the easiest way to see what you face is to take the time to learn how to do the tedious math yourself.
One of the better options at your rating is to seek TDIU. Learn more here.