b.t and internet, exchange congestion?

[martidj2003]

hi, i have been with bt for 1yr. and over the last few months my internet speeds have dropt. called bt they say everythings fine. i only get 1meg at the best of time, but come peek times it drops, hell of alot, cant use my ps3 online im paying 24.99 a month my exchange is doncaster and has been congested for months, and the funny thing is bt keep puting the date back for upgrade, but still adding more ppl on, and now im startin to think they are capin everyone to stop congestion, this is making me so bad what a rip off i should be on the up to 8meg. bt say i get 2meg but all the test i run say 1meg. when i phone bt its like they just read off a screen and they dont have a clue, i see bt going on about the 21cn but how fast are they going to be in getting the exchanges upgraded,, soz for me spelling