Yesterday i just booked my first EX-EU ticket from DUB to MCO for september MFU from WT+ to CLUB with a stopover for a night in london both ways when i went through booking it stated for 2 passengers it was 50000 points for the upgrade.

But on checking my eticket which i have printed of it states
Mileage debited 50000
then below this it states Additional mileage 50000

But i have only been debited once any ideas what this means
im i still due give a further 50000 miles ??