I have some dried arbols that are at least 10 years old and they are fine.

My personal experience w/ Thai Hots (if left in a covered container in a cupboard) is that they will last for a few years losing some of their heat toward the end. If you vacuum seal the flakes/powder they will last for many more years.

Cherry peppers however, are much fleshier and considered a canning pepper as opposed to a drying pepper. I have not had any experience drying them, therefore I can't comment. If you used a dehydrator as a means of drying them rather than the standard "air drying" method, I believe your success for long term storage would be greatly improved.
A percentage of thick fleshed peppers that have been hung and air dried have a tendency to generate bad micro-organisms and may rot or get moldy/spoiled before they fully dry, even if good air circulation is provided.

In any case, vacuum sealing if definately the way to go when looking at super-long term storage.

Just my 2¢.

Thank you both for the wonderful advice. What is the concensus on grinding these peppers?

Thai peppers can be easily ground making wonderful flakes/powder. Cherries on the other hand; assuming they are completely dried can be ground.
Again, I have not had any experience w/ dried cherries but if they are not fully dried, it will be messy and a failure.