I have about 200 keys from a 3rd party offer I did and was going to use them on the previous promotion for all the bonus exp but ran out of time before the keys showed up on my acc. I am not really interested in this new promotion. If I wait for the next promotion, will I still get my daily keys as normal which I can use on the current promotion?
If you've earned keys from skilling or through another method, yes you can save them.
For example, players received 10 keys from the festive calendar this holiday. A daily key of +1 (F2P), or +3/4 (depending on if standard member or premier club) would add on to that count daily. So in this scenario, you would have 11, 13, or 14 keys at reset (depending on which of those membership statuses your account falls under). If you use your daily keys, you'll keep your saved keys/earned keys (from quests, offers, etc).