From SHA to city of Hangzhou., besides trains, are there any long distance buses?

We'll arrive at SHA on 25th Sept evening, are there any high speed train tickets to Hangzhou available to purchase these days ?
notice there are many high-speed trains departing from Hongqiao railways station, every few minutes there is one, are they all fully booked ?
If all train tickets were sold out, what is the alternative to go to Hangzhou ? is there any long distance buses
leaving the area ?
thank you in anticipation to give us the answers.