After speaking to someone at the ticket office, I can't say I have a massive amount of confidence in the moving seats policy. You have to fill in a sheet that gives you just 3 options for seats you'd like to move to- which would be ok if I thought that the Ticket Office staff had the common sense to also look at the seats surrounding these seats. They are then entering them into a spreadsheet, which will be looked at on Monday 24th on a first come, first served basis. The bloke then told me that if one of these seats wasn't available, they may phone me and let me know (which I assume would allow me to look at others around there) or they may just not [bother], in which case I assume theyll just leave me in my current seat and move on down the spreadsheet. Needless to say I'll be going down there again on the 24th.