Right, will try to remember as best i can (was a coule of years ago now!) and hope it hasn't changed too much!
We arrived, bleary eyed bright and early, and got given a full tour of the place - taken around and shown each and every therapy/play room. tbh, this was not particularly helpful for us - yes, it did show us th elayout of the place (but so would a map!) and it was confusing for dd1. we got taken everywhere, shown in, shown (for eg) how the music/lights/play equipment worked, dd1 was encouraged to have a go and get familiar with it, and then we were moved on to the next room. We did mention in our feedback that this was not perhaps the best approach to take with an ASD child, so maybe they've changed it? If we go again, we would ask not to do this.
We then had a meeting with a doctor, who took a case history and asked basic health questions. Did height/weight check. broad diet rundown. quick overview to make sure that all would be ok in each therapy room, I think.
Then we got down to the fun part. We had 2 therapists who were "ours" for the 2 days. And in between seeing the SALT and the dietician (both extras we had requested) we did a full development check on dd1.
Lots of guided/structured playing with one fo the therapists while dh & I answered a million questions of dev history. Exhausting but thorough.
In the course of this rundown, we moved through different therapy rooms, so when checking physical development we were in a softplay/indoor gym type room, so they had all the right equipment on hand.
they have a big room where you can have lunch - use of microwave there, iirc, and there are juice/yoghurts in the fridge. kettle for tea/coffee etc.
It is avery full couple of days, and we were all exhausted, but it was so worth it. they were billiant with dd1, and we had a very good home programme which helped her loads.
and their report remains on of the most thorough and informative we have ever had (they check details such as eye tracking/competence in handedness/ear dominace etc, as well as the more obvious developmental/sensory things)
Hope that helps - if you have any questions, please do ask and I'll try to answer them