I'm assuming you mean the one at Nottingham HQ on the 17th/18th? I'm going to this, taking double goblins. Hope to see you there!
Given my experience with GW tourneys is that they often don't allow enough times for turns... Doubly so in a doubles tourney. You really need a combo that's going to smash face quickly in order to rise to the top.
This. Make a spread sheet of rules you need to refer to often(miscast table, Errata, Alliance rules ect) This will speed up the game. Also make sure you and your buddy can move your miniatures table to table quickly.
I have to be honest, I've been to all of the last 4 doubles tourneys run at Nottingham and this has never been a problem. They have always provided more than enough time for games and between games, the minimum between games is 30 mins between the 2nd and 3rd on the saturday, the others have over an hour for lunch between them! Most people have time to find their table, put models down, go to the bar and even start deployment before the game time starts, and the 2 1/2 hours for each game is ample.
The tourney itself is rarely competitive, there's the same 4 or 5 teams each year who dominate the top 6 tables then after that most people bring fun lists, and no one take sit mega seriously its really much more of a fun tourney.
Posting the list would be fine, no one is suddenly going to taylor their list to try to beat you on the off chance that they play you in one of their 5 games against any of 100 or so teams. Also as I said its not in any way a serious tournament so no one is going to learn your item combos to try and gain some miniscule advantage.
Our list has 120 night goblins, 7 chariots, 2 pump wagons, 2 Manglers, a doom diver and a troll... and the wizarding hat. Just got to hope it all behaves itself!
Step 1: Black coffee.
Step 2: Guinness.
Step 3: Play Ogres.
Step 4: Return to 'Step 1'.