Purchasing improved warranty

[fixit]

Hi,

Have been asked to advise a friend who has a T500 - Type:2243 Model:7RG, purchased in Sept 2009 in the UK.
It has become quite noisy which is clearly the fan bearing, so a warranty call is required.
He is registered blind so is very dependant on the machine. The standard waranty is 3 year Return-to-base and he has been quoted 7-10 days period before return to him from Lenovo UK's service contractor, which is not really acceptable.
He then went on line and discovered he could buy a warranty upgrade to 3 Year Onsite Repair 5x9/Next Business Day for about £70 and so he bought this option.
What he's wondering is what happens now? I'm not familiar with this proceedure. Does he just ring Lenovo again straight away or as the websire implies, will he receive some form of "product" needed to activate the upgrade?
Is it just this simple or is he going to run into some "Terms & Conditions" problems about applying it to existing calls?

Thanks for the help in advance!