we did the SS two weeks ago and it was fantastic! yes, only open to concierge guests of AKL. it is a bit cheaper for kids ( i don't remember off hand!). you meet in the Kilimanjaro club the morning of-- to register and you can have a coffee. then we met in the sunset overlook - this was at 715am. then we boarded busses about 730a. drive over, the back way, to AK. this itself was interesting too. had a expert on the bus. then we did the safari which lasted an hour. it's a nice slow pace, with plenty of opportunity for pix and questions.
then a FANTASTIC breakfast buffet at tusker house- and you also get a fast pass to do it again.
it's on sundays and thursdays.
highly recommended!!