The ARP is the window between the day booking opens and the day of travel. For regular trains it is 60 days, not counting the journey day, and reservation opens at 08:00 IST on the first day. It was 120 days until 31 October 2024; the Railway Board cut it to 60 to reduce speculative bookings and cancellations.
The Foreign Tourist quota keeps a 365-day ARP, Tatkal has its own one-day window, and special trains open on whatever date their notification says. A handful of short day-time expresses also keep a shorter ARP of their own.
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