Bus home issues

My 17 y.o gets the bus to and from school everyday. It is a public bus. She is absolutely fine in the morning, most of the time, but the way home she struggles. 

Staff will walk her to the bus stop and most of the time will leave her to wait. This makes her feel really crap. Days when she leaves school not fully regulated are the worst, sometimes her mental health can deteriorate really quickly and she can have a crisis after staff leave. 

I don't think the waiting is much of an issue but staff leaving her is. 

During school if she is pacing the school, not working or in a safe place, any room, she will be sent on the bus home. This is now making her feel she cannot express or feel emotions and masks greatly. It is also affecting her mental health because she doesn't feel wanted or cared for. 

She has a tablet with a communication app on and a whole bag of sensory toys but it seems like they don't use it as much as they should. She doesn't want to take her bag anymore either but I'm making her. 

I don't know what to do about the bus situation. The bus after school finishes the journey half way home so I pick her up from there everyday. I have tried phoning the school to discuss staff leaving her again but had no luck with them answering so going to talk to her tutor in the morning. If they do turn round and say they can't stay with her for whatever I really need a back up for her but don't know what so any suggestions are greatly appreciated! 

Many thanks in advance