Hello all,

MY first itinerary ends with BOS-YYZ, where the second starts with YYZ-ORD. Both of them are under UA tickets but AC operated. Is there any chance that I can change this BOS-YYZ-ORD to nonstop BOS-ORD per same-day change option?

(Just for the curiosity's sake, what if both of them are UA ticket/metal? Will it be more likely?)

(BTW, should I fly BOS-YYZ-ORD, must I clear both Canadian and US immigration?)

TIA
edta450