Three of us booked in PY Flex for YUL-YVR for Feb 20th, waitlisted at time of booking (Feb 12th) and remained so.
Looked yesterday at other options, used my usual filters of eupgrades, equipment type and earliest arrival.
The flight we are already booked on showed the green upgrade eligible for Latitude but not PY, was quite surprised.
Cancelled eup requests and put them back in to try and trigger an upgrade from the existing PY Flex ticket. No luck.

Booked three new tickets in Latitude, confirmed eups right away, picked seats, cancelled PY Flex tickets, pocketed some money in the process.

From an AC POV, why does it make sense to not confirm eups from PY Flex but will confirm from Lat?