I don't know whereabouts it came from but I looked at an imported GTI in here the other day and it had manual aircon

. Silly things like this could cause big problems on re-sale! Best advice is either buy from a main dealer ( like me!

) or just check every little bit of spec before you buy. UK spec can be taken in several different ways. MPH speedo and right hand drive could be what some people class as UK spec!
UK dealers pre-register cars to make up their numbers. Usually at the end of a quarter (March,June,Sep,Dec) because targets are calculated on registrations. If they hit their target they will get a bonus from VW pre-rata for each vehicle. This allows them to then offer attractive prices on selling pre-reg vehicles.
With imports, they are often pre-registered for ease of the importer. They buy 100 cars for example and they get registered in their name (trade sales Slough, motorpoint etc) as they are the customer. They then get sold on as 06 plate delivery mileage cars. Nothing really wrong with it as the amount of owners doesn't really make much difference in a few years.
There are other forms of pre-reg cars with car brokers but that gets really complicated.
hope this helps you
VWmd