SBC - Kranti Veera Sangolli Rayanna Bengaluru: Station in Garden - Dinesh Kumar

Can anyone confirm how many seats are available from Tatanagar to Pune on the HWH-Pune Duronto Express (12222)? I can see only 7 seats are available from tatanagar, where as more than 280 seats are available from hwh on IRCTC website.
Want to purchase three ticket which must have to be lower birth? Is it possible to book ticket from tatanagar to Pune for all the three tickets as lower birth among those 7 available ticket on 1st December, 2016?

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