Servisair have special contracts call AD-HOC which means they can call upon you when they are short staffed (which is all the time usually) and when they need holidays covering. You could try and get them to put up on one when you go back to uni, so you should get a few hours a week that can fit in and around uni.
yes the pay is !!!!, but at least ull probably be earning a bit more than your other student mates as most of them will probable have !!!!ty low paid bar jobs. Also you get a job which involves some real responsiblity and you get a foot in door in the aviation industry.
Cheers