Good point Zoltan! Believe it or not I didn't even know it was available!
I received a letter of invitation from BMW to take out the extended warranty just before the manufacturing warranty run out. It is worth inquiring why they didn't send you one?
Just had a look on the BMW warranty and the alternator is covered...As the dude said, if your local dealer is any good, a good will contribution should come your way, if that doesn't work BMW UK next port of call.

