I called the other day and asked to be setup for a platinum challenge (18 nights/3 months). I'm currently MR Gold. I went to check into another Marriott yesterday and was asked if the points were what I wanted for my arrival gift...slightly perplexed I just accepted the offer. After getting back to my room I logged onto my MR account and noticed that my status was upgraded to Plat!

Is this standard with the challenges- that they upgrade you for the period of the challenge and then you lose it if you don't make the 18 night requirement, or was mine just a fluke?