Promo bids are a pain 90% of the time for that exact reason, they expire. They can be useful if there is something you want to bid on NOW. While I was still very active in this game. If I wasn't really interested in anything and had a lot of promo bids, I would use them on an item that wasn't popular but I or a friend could use. Using them mainly just to gain a bit of experience playing around with different methods of bidding. The cherry auctions are there just for new members so that you can be sure of bidding against other new members that are also learning the ropes. Items locked are auctions that haven't begun yet, but shown so you can set a reminder so that you are notified when the item you want goes up for auction. It's been a long time since I was active, more than 6 months, and I still get the occasional reminder that an auction I set a reminder for starts soon. A long answer to your question, but yes it does severely limit it for you. That was one of the things that drove me crazy. All I could come up with, was that they hope you'll settle for another auction of something similar or just not use the promo bids.