For those of you wondering why you couldn't book breakfast for CRT in August and later, the problem seems to be fixed - lots of availability in late August and early September, based on some spot-checking.
I was about to post the same thing! Had checked at 180 day mark and got nothing. Today I thought I would just try again (had booked lunch at d180 but really wanted breakfast) and "voila"! Last year loved entering MK before opening - was just very cool to walk up to an empty castle! Wondering if they're still serving that new "breakfast bread pudding" -- looks like dessert for breakfast!