Check with the bus office at SAS for large pick-ups. We arrived in August from the US. When I went to the SAS bus office in early June (before school was out for summer), I was given a list of bus stops and the bus office ticked which pick-ups had multiple bus-loads of SAS kids.
I would check-out: Four Seasons (they have 3 buses of SAS kids which means more than 100 kids). Four Seasons is Orchard Area. There are a few other buildings adjacent to the Four Seasons (names escape me as we are new here). Also, Arcadia
condos (Bt. Timah Rd area) has 3 SAS buses so many SAS kids.
Good luck!