Earlier today I was doing some voodoo with the servers to streamline when the cache gets sent to you via the FastDL and basically it's now working so that if there's a cache update you shouldn't have to rejoin to get it now (you should get it first time). This applies to all gamemodes and requires no more interaction from my end to update the cache. So if Wire magically updates on BBuild now, you won't have to wait until I get up to be able to play on it.
Just an update to this, I've got it working properly now so auto-update for the svns on BBuild is re-enabled (but the auto-cache system is live on all servers otherwise).