Maybe you should speak to their tech support because this is what I just got at pretty much peak time: I'd like to see someone using BT or any other ADSL ISP for that matter getting a 24ms ping.
It'll be a costly 09 number and he'll likely get put through to an Indian callcentre, unless that policy has been changed.
As for the ping, 24ms is nothing special. I've gotten lower than that prior to the ADSLMax\LLU rollouts on a 1mbit service...