Hi,

A few months ago I booked a 50% off YYZ-BOS weekend away / segment run

I booked Saturday Nov 17

AC 416 YYZ-YUL @ 3pm
AC 7686 YUL - BOS @ 5:55pm

Return

Sunday November 18

AC 8049 BOS-YOW @ 3:50pm
AC 463 YOW-YYZ @ 6PM

Now, looking online I see several schedule changes:
No more AC 416, replaced with 418 that leaves little time to connect on 7686

Return

8049 now leaves at 5:50 instead of 3:50 and would miss 463

My questions:

How flexible are my options to change my reservation given these schedule changes?

I'd like to:
Maximize segments
preferably leave from YTZ instead of YYZ
Leave Friday instead of Saturday

What should I know before I call?

Thanks