Mobile Share Advantage Plan

I've had the mobile share advantage plan for two bill cycles now.  I hit my limit last month and was not throttled but according to the myat&t app I was charged.  However, I was never charged for the overage package.  The most interesting thing is that only the myatt app itself says I have an overage package.  Again, I have never been charged for an overage in the last bill cycle or the current bill cycle.  All is good there.  Notice how visiting the mobile myatt site how no overages are shown and it says I'm throttled, same situation with the desktop website.  Now the thing I'm NOT complaining about is that I am not being throttled.  I was just wondering if the throttling feature has not been operative yet since this plan is so new.