Hi there

Newbie here so have a question / clarification on e-upgrades when checking in.

Assume that one has requested the e-upgrade 5 days before the flight and has been waitlisted. Now it's time to check in 24 hours before the flight.

1) When you check in online on AC website, there is an option to "eupgrade" during the online check-in process. Is that step mandatory in order to be on the gate waitlist? Or can you just let it "slide through" and maintain your spot on the waitlist?

2) Is there any advantage to checking in online early for e-upgrade purposes when you are already on the 5 day waitlist?

3) What happens when you check in via a connecting flight? Specifically, if I am flying from Rome to Frankfurt on Lufthansa (AC codeshare, LH metal), and Frankfurt to Montreal on Air Canada (AC flight). Given my starting leg is on Lufthansa, I assume I have to check in on Lufthansa's website - and I assume Lufthansa's website won't have the e-upgrade option there. How does the eupgrade process work?

Cheers