Long Layover Change

I booked an international flight a few months ago. I know that departure times can frequently change, especially with booking in advance, but my layover went from 2 hrs to 7.5 hrs at YYZ. I don’t see any other available flights and I had an AC credit I needed to use.

Any tips for a long layover at YYZ? Would AC offer lounge passes if I ask? I’m a frequent flyer on other airlines but I’ve never flown AC so wanted to know what to expect before calling. Thank you!