I'd be very happy with an empty seat next to me if it turns out it's not full. An upgrade would be nice, but just the ability to sit with my back flat against the seat would suffice.
It doesn't look like seats blocked for balance reasons. One minute it was busy but with a fair bit of free space, then suddenly nearly nothing is free. Each cabin section has one, max two single seats available.
Incidentally, on the flight over there were a LOT more seats blocked on the seat map than actually taken on the flight. Either half economy class did a no-show or Emirates blocked empty seats. Again, I'd be surprised if this was balance as they were blocked from 2 weeks before flight.
We'll see
i still have fingers crossed for an upgrade, but that empty seat will be more than sufficient