I have 1 year NCB, but I've officially passed my test 9 months ago. I've got my eye on a GTI, but the difference is enormous between someone that passed exactly 1 yr ago, and 9 months ago.

£1441 for me (9 months ago)
£760 if I had passed exactly a yr ago.

This is so frustrating. Do I have to stick to my 1.4 for the sake of 3 months?? What should I do??

I imagine the stats are that you're an increased risk until you've been driving for a year, hence the increased premiums. If you can afford it, pay it. If not, and shopping around doesn't turn up any better deal, then live with it.

So if I stick with my car for another 3 months, then when I'll have been driving for a year they'll still give me a decent quote??

that's up to them. they are a business and so can charge what they like.

In the meantime have you tried giving Adrian Flux (http://www.adrianflux.co.uk/hot-hatches-detail.php) a ring?

They're basically a broker who specialise in 'performance' cars (the link above is to the hot hatch section).

You need to ring them. They don't do online quotes.

They saved me 35% on the next best quote I could find on the web.