I agree withh1ghflly3r J/F redemptions are far better value than upgrades And the cash plus miles option is excellent. Meaning you only have to have 75%of miles and can pay the rest as cash, but still a fraction of what an out right cash seat would cost
It costs over 70000 miles to upgrade a return flight AUH-DUB but only just over 90000 to redeem a J seat. No brainer in my opinion considering a y ticket on the route starts at about 600 euro!