I don't have any inside info on the parameters being used.
But, a reasonable guess would be that:
If there is any tailwind component on 16, i.e. any breeze from the North, the mission will be scrubbed. [Rwy 34 isn't suitable for landing a 747].
Additionally, there will be very restrictive crosswind limits also. Max 10, or even 5, would be my guess.
If the runway is not completely dry, the mission will be scrubbed.
Don't assume it is just all going to happen at 7.50 this Sunday. A lot has to be favourable on the day.
[Perfect conditions would be 20 knots of steady Southerly straight down the runway, in my opinion. Like landing into Wellington, NZ in the -SP, back in the day, wind is your friend. Up to a point.]