Last time I rang I initially spoke to a call centre in India, then promptly got transferred to somebody in Glasgow. I bet the personal customers stay on the line to the Indian call centres
Its the warranty rather than the customer type that routes the call. For example a latitude with basic next day will go to india support, even if you buy a lot of them. A latitude with Pro-Support / Dell Business Support / Gold + above support will route to Glasgow, even if you only buy one of them.
I guess someone at your office bought what would have been Dell Business Support at the time. Which is a very nice add on – not so much for where you speak to – at the end of the day next day support is next day support whether you speak to Glasgow or India, but the add-on allows a limited amount of best effort software support. This boils down to we will help you with whatever you want software wise, as long as we have the capacity (ie we don't have a lot of calls queuing). Way back when I used to do that support (5 years ago now!) I spent many a happy hour setting up bluetooth links with mobile phones, helping people with excel spreadsheets, setting up word templates etc. You also get a named tech dealing with your issue – so you have a single person to email to chase for updates etc rather then needing to call in all the time. Personally anything I buy from Dell has pro-support on it.
If you have a pure consumer product (studios / inspirons etc) then I don't think you can actually buy pro-support for them so you would always route to India.
***Disclaimer***
This might all be wrong and is certainly open to change at any time!
Many other laptop vendors are out there – they certainly all offer the same level of support if you pay for it.
David.