Fixed term interval is 10k miles or 12 months, whichever is soonest. Variable interval is designed for the higher milers, and you could see up to 18k miles between services on that regime, but if you are doing so few miles, chances are that the car will ask for a service significantly sooner than the time it would take you to run up 18k miles (and the shorter journeys that you would do would prompt the car to knock the interval down anyway on an oil quality monitoring basis).
Is the BMW harder on all 4 tyres being rear wheel drive? Chances are, you would be only looking to replace the fronts. You’d comfortably be around 6mm tread on the rears after 18k miles/2 years on the Golf.