I'm not 100% sure.
I don't have EF. If I only see 2 J seats for sale I assume it's J2.
I was travelling with a 25K who was #3 on the upgrade list but never cleared.
His name was never on the app. The agent swore up and down his name was on the list.
Even showed me the screen with his name on the upgrade list.
An hour before departure the app was showing 36 people checked in for 40 seats.
At closing the app showed 4 people upgraded, but the 25K's name was never displayed on the app.