Originally Posted by
Ozziebob
I continued on to DEL and as jackiedada states, this is not available in India, so you just have to wait and (hopefully) get surprised at the gate
You can still do it through the website, but don't do it through Manage A Booking.
Go to "Check In" again, even though you have already checked in. I can't remember the exact sequence, but as you progress through this you'll see your seat number and it will disappear if/when the upgrade happens.
This must be almost immediate as I entered the lounge in DXB a few months ago - no mention of upgrade. Within a few minutes I powered up my laptop and saw the changed seat info so headed back to the entrance and picked up a new Boarding Pass.