I'm probably the wrong person to ask - not a total fan of that restaurant, if I'm being honest. But of course, it's the castle and all that so I get it. And despite my comment, we'd still go again.
Your timeline seems reasonable to me, although I don't have enough experience there to know if they often run late or slow. Hopefully someone else can chime in with experience, or maybe try posting on the Restaurant board if you don't get much info here.
Have fun!