From My Guess, it's Like this way..
For Remote Location Stations.
As Many of us have Doubt's of CK Availability are Increased Most of the Times.
When u book Tatkal Ticket from Remote to End Station.
As...
more... Normal CK Gives Avbl 6 in this Train from PNVL--ASR
As Soon as CK Starts from Originating Station KCVL it's Allows 158 Seats Something for CK Booking. Today this Train CK Starts at 10 Am (Same for PNVL/KOTA/NDLS) Now U may book your ticket from KCVL---MAO/PNVL/BRC. Then the Remaining unbooked BerthS goes to Either PNVL/BRC Quota, then this Avbl 6 (From PNVL) Increase to Avbl 7 Same with further CK Booking. If u booked till BRC/KOTA/NDLS and that remaining unused berth automatically goes to further Quota (KOTA/NDLS/UMB) anD the CK AvaILability Increases instead of Decreasing...!!
e.g.
KCVL--MAJN:- A Pax Booked CNF Ticket. Then this CNF Berth will be allocated by system in PNVL/BRC Quota as per the Availability
KCVL---MAO:- Same as Above.
KCVL---PNVL:- A Pax Booked Cnf ticket now PNVL After this Berth will be allocated to BRC/NDLS Quota.