40+ Y flights a year and I've never not had my first choice. However 80% of those flights I sit in the front mini-cabin on the 77W (rows 17-21).

I've once or twice been told they didn't have my first choice, however each time I simply responded politely "I'm happy to wait until you finish the service to see if there are any left over in other sections."

Quick one about how EK provides service in Y: They load the hot meals into the cart and cover it with the box, the cart is good for X rows, and another cart will often begin service X+1 rows ahead, i.e. if they calculate that the first cart will have meals for the first 20 rows, a 2nd cart with other FAs will begin service from row 21 onwards simultaneously, so you could get a meal mid-cabin before the 5th row from the front of the cabin gets it. Also of course service is conducted in parallel on both aisles. In total on a 77W I think there are 3 or even 4 carts per aisle (same carts used twice though, so not 8 distinct carts, but 8 "runs"), each has some kind of split of the meal choices. If you're told they're out, what the FA usually means is his/her cart is out, so either ask them to check "in the galley" or say you'll wait if they're adament, and usually something shows up.