I arrive later to Xian and I need to buy three tickets.
First: High speed train to luoyang G2002
Second: High speed train from luoyang to Xian.
Third: Xian - Pingyao. 2672.

My questions are: Is it possible to buy all these tickets in Xians Hall ticket main building?
Is window 28 ticket seller especially for high speed trains opened at 0h30min?

Thank you