Originally Posted by D582

Not quite. In the certificate days, Reservations would process upgrade requests as of 00:00 in the local time of the departure city because they based it on 'days'.

For example, a SE flying Tango Plus YVR-SYD on the 8th at 23:45 could call in on the 1st at 00:00 (YVR time) and process the upgrade request as anytime on the 1st would be considered T-7 days, even though this is almost 8 days out.

The website function to request an upgrade (when it actually worked) would enforce the window based on hours (like eUpgrades) and therefore would only open the window at 23:45 on the 1st.

This gave a distinct advantage to elites who knew this loophole to secure their upgrades.