Just figured this out on our last day here. If a kiosk is telling you that a premium ride is not available for a FP until 1025pm, take it anyway and then periodically try to update the time to earlier in the evening using the MDE app. We ended up moving up our Thunder Mountain FP time slot to right after Wishes. No having to wait until 1025pm. We'll probably catch the MSEP on the way out as well.