Just going to jump on this bandwagon for a split second, having a quick flick through some of the posts here regarding the original thread.
Some of the posts here and advice is so so shocking.
I applied to a TOC and I did not put a specific depot to work for, I did however state from the off that I would relocate, this is due to having to live within 45 minutes of your depot, I lived more than that from even the nearest depot that I could of had chosen, the fact that I wanted to be a train driver, the depot was not an issue, at the time of my interview with two station managers I was living 85 miles or at least 1hr 30mins from the depot that the TOC chose for me, I was asked how I would get to work at any time of the day and my answer was simple, I drive, and I am moving to within 45 minutes of my depot (I have a place now 40 mins), I was asked about relocating and was informed by the manager that my depot was in a location that was very expensive, that is why I am not in that exact location but within 45 minutes.
My point is that if this is something that you really want to do then you will do it, but please think about it plan it out, organise it and be prepared, you will not get employed if you show no flexibility and commitment, this will be a put off from the start and will not go down well, getting a taxi, riding a pushbike 20 miles, kipping on your mates sofa for the night is not what is wanted, and asking for a shift swap is no good as the chances are you will not have only one 3am start but many, there is a reason TOC stipulate you live within 45 minutes, think about that and the reason WHY!!