High speed train (Beijing to datong)

Anyone has update when the high speed train will start to operate? As I intend to fly in BJ and travel to Datong in 23 October.
My current option to travel to BJ to datong is:-
1. By flight - But need to stay a night and catch the morning flight and ticket not cheap
2. By train - Travel from airport to train station very taxing to train station and travel 5-6 hours to reach datong
3. By Bus- About 90min journey to Bus station and travel about 4 hours to Datong.

Or it is better to travel from 1 Nov on wards to catch the High speed train.
Thanks for any advise.