QUICK - 2lb loaf cake recipe in 1lb loaf tin - Timing?!

[loomer]

I've just made up Bill Grainger's lemon drizzle loaf cake from the latest Delicious magazine - but have realised that I can't fit all it in my loaf tin - the recipe calls for a 1kg loaf tin, and I read it as 1lb . Therefore I've put half the amount of cake mix into the tin.

Any ideas on how I need to adjust the cooking time? Recipe calls for 40mins, then cover with foil and a further 20mins.

Well, just for future reference, it took 40 mins plus 15 with the foil on. So I have two cakes. And they're quite delicious.