Funny you should menion that. One of the vanes on the impellor inside my compressor recently sheared off and locked the compressor. As a result the pully which drives the compressor and which is driven by the fan belt locked resulting in a broken fan belt. My first warning was a squealing noise for approx. 30 seconds and then the battery warning light came on.
A quick look in the engine bay revealed the broken fan belt and locked pulley. Happy that I was not going to do any more damage I drove on the the nearest dealer about 20 miles away on battery power where I was supplied with a courtesy car as they did not have a compressor in stock. A new compressor arrived next day and was fitted under warranty without quibble.
My car is approx. 30 mts old and has 30,000 on the clock.
Hopefully you get the same sort of service.