Looking at a YVR-YYZ redeye.

J is full.

I'm on an unlimited Latitude flight pass and am within the 48 hour upgrade window

I'm watching Expertflyer for J to open up (48 hours), but currently back in economy.

Since I've never had this before and have never had to upgrade to PE:

- should I upgrade to PE using certs?
- if J becomes available, will 'undoing' the PE upgrade screw up possibly timing to grab J should it instantly become available? I know they often disappear in seconds