प्रयागराज एक्सप्रेस - जो भी हो तुम खुदा की कसम; लाजवाब हो

Train that I booked which is 12687 - scheduled to leave by 23.35 PM (27/12/2017) is rescheduled to leave by 5 AM Tomo morning (28/12/2017)
At what time will I be able to file TDR ?
I booked via Tatkal - will I get the full amount as refund
How many days will it take for the refund ??

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