I don't think this will work for challenges. You have to sign-up for a challenge, it doesn't happen automatically. So, assuming that you only signed-up for Gold, and still made enough pints for Plat challenge in the 90 days last year, you still would not get Platinum. So I don't see how you would get it now.
But stranger things have happened.
Also, I do believe the accounting will be done next week by AA and the new status levels should start showing up some time after. Either it will never show up or you may get a nice surprise one morning. I don't thing calling will do any good.