An ETA; no. One of our users was kind enough to lend us their account to diagnose the problem, and we've pinpointed it. Whenever you have a lot of vehicles in the garage, it takes quite some time for TankLeader to go through all them, especially if you have like 90 vehicles in the garage. Where it takes 1 second to go through all of them, and queue for a battle on my accounts, it took up to 20 on the account I tried it on (75+ vehicles).
I am currently thinking of measures to make this entire thing go faster, and might even end up changing the entire queue system from a priority-based system to a circular queue (queue with set tanks in a set rotation), but I'm not sure if that's what I want to go for currently.
I'll get back to you guys when I have thought out how we're going to fix this, but for now, we know where the problem lies.
Ps. It's very, very machine specific. It worked on my machine, but I'm running an i7 3770k at 4.8GHz, with 32GB RAM, which could be considered a high-end system. Machines with less power will take more time, and could cause the game to freeze before even finishing.