On return to Bulford, contact Tidworth Tp, 721 EOD Sqn, 11 EOD Regt RLC - I will PM you with names & contact nos. Go & see them, the guys there will be able to explain how the AT selection & re-trade process works and you'll be able to chat to them about the different roles that ATs have within the Army.
Within the R Sigs, you may have heard from some of your collegues who worked as ECM Operators with EOD teams. There is more to being an AT than just IEDD, however glamorous that may seem!
If you're able to speak to any of the ATs/ATOs out on TELIC at the moment, they would also be able to give you a feel for what life is like within the trade.
I changed trade from Driver to AT in 2000. The course is not easy, a lot of info to learn. Course is 6 months long, you then wait a minimum of 2 years to do Upgraders, another 5 months long. Plenty of other courses to do along the way. Tidworth Det has a couple of re-traders there. Speak to the 2 Stripeys there, sure they will help. Like any job, it comes with plenty of b......t but the faster promotion etc can make up for it. If you don't try you will never know. Good luck.