Thanks for the help, everybody!

In the end, I decided to change the flight altogether. I had originally paid 646 EUR for my ticket, but now there was a sale going on for 398 EUR the same ticket. So even with the cancellation fee, I came out way ahead!

I booked the later flight out of Dubai on the A380 and then upgraded both of us to Business with miles.

So much for keeping the original flight and hoping for an upgrade. I would've been upset if I had kept the original flight, but not gotten an upgrade after still having paid so much more!

In any case, I appreciate all the advice!