My cub has just had its first service. It is a P250. Checking the oil level after the car was returned I find that it is only half way between the upper and lower marks on the dipstick. The car was filled to the upper mark when it was new, but the dealers tell me that half way is correct. As I am just about to embark on a 1,500 mile trip around Scotland, does anyone know what the correct level should be? The handbook suggests topping the oil up once it drops below the halfway mark.