nana

If you have to ask, it's probably not enough. I realize everyone's circumstances are different, but it seems like you're trying to skate by on the least amount of effort. Do your best, and good luck!

Prove your dedication and have the humility to start over at white. 20 years is a huge gap and even if you still "got it," your new school is going to have its own curriculum that you're going to need time to get up to speed on. IMO, people who come into a dojo wearing a belt earned far removed, be it either by time or style, unnecessarily disrupts the order of the dojo. If you go in with a high-ranked belt and don't have the skills to match you're just insulting all the students who have put in the time and effort to get where they are. If you catch on quickly and have a good instructor, you should get advanced faster so long as you're meeting the school's expectations.

Absolutely this. Just keep up the best you can and keep showing up consistently. Even the skinny beginners struggle at first.

I started Tang Soo Do last year with no previous martial arts experience and ended up skipping belts at my first test. Although I was held at white belt for about 5 months. In the early ranks our instructor gives you what he thinks you can handle, so the lines between the curriculum you're expected to know are a bit blurry. After what was supposed to be my gold belt test I was given a purple belt (the next step up). At this rank I've been allowed to do some of the more-advanced kicking, but none of the other curriculum elements that are above my level, so there definitely won't be anymore skipping. My first week of classes as a purple belt I was slightly intimidated by myself because it occurred to me, "Oh crap, now I really have to prove that I deserved this." And I realized that getting promoted is only partially about proving that you're proficient in the skills and techniques you're expected to know; it's also about proving that you're ready to learn more.