Heidi, the last time I bid I placed a check mark in the box of the zone as though I were going to bid. When I went to the next page, I then was able to see what levels were offered. I do that for each area I bid in - going back and forth to check.
Have you been to TravelSheryl's website? She explains this under Hotel - FAQ #12. Before I bid on Priceline I always check out her FAQs to see if there have been any changes. She's very good about keeping things updated.
Enjoy using Priceline! We've enjoyed all of our hotels!