I've ordered the T-mobile contract with MPD and am patiently (well, actually not so patiently) waiting for the device to come through. This is the first time I've ordered a contract online in the UK so not sure exactly how it works. I understand they will charge me the £3.99 for delivery when the device is ready to ship, but what exactly happens about the monthly £35 charge to T-mobile? When exactly is that debited from my account? Immediately or later?

Any clarification would be helpful - I've been living abroad using PAYG for a long time so I'm not exactly familiar with the charging system for contracts in the UK.