I had the reverse problem when I took my car from France to Coventry. In the end I couldnt find the switch and just lowered them a touch and no problem.
Where are you in Surrey? I used to live in New Malden, school in Kingston and pub all around Molsey, Esher down to Walton. Those were the good days..
Adjusting the headlamp pattern for dipped beam from right to left-hand traffic and vice versa is carried out in the SID in MY08. Too bad that option doesn't apply for MY07.
Further to David Morgan's suggestion, there's a knob under the hood, right next to the dipped beam buld. Turn that clockwise or anti-clockwise and see what happens.
I spent almost a year in Guildford back in 2000. As David put it, "Those were the good days" indeed.