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@Dipyaman Basu*: Re# 97391-17
Need example for diff PQ Quota in Rajdhani/Express for same day journey!!
RL Quota can be guessed, bt not PQ Quota.
Its all so complex
eg. LTT-ALD - Booking happen in...
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GN & PQ Quota, for trains like Godaan (GNWL & PQWL can be seen)

@Vinay Kumar: Re# 97391-14
Starting Station: A
Intermediate Station: B
Destination Station: C
Terminating Station: D
From...
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A-B, A-C, A-D (GNWL).
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RLGN
If ticket is purchased from B or C (for journey from B-C-D or C-D , and if B or C are imp places then the ticket wud be in RLGN, and subsequently would go to WL.
(Note: In some cases, where the station shares less quota, it can be clubbed with GN Quota after GN Quota exhausts and/or to exhaust the RL Quota).
(Considering the above point, Journey here can be from A to any station).
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PQ
If a train passes thry B-C(starts at A , ends at D) and if the demand of the train is high B-C can share a PQ for this train. B
Journey can be:
B-C-D or C-D
This is to prevent complete booking of this train from A.
(Note: In some cases, where the station shares less quota, it can be clubbed with GN Quota after Gh N Quota exhausts and/or to exhaust the PQ Quota).
(Considering the above point, Journey here can be from A to any station).
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RLWL
When the intermediate stations do not have any RL/PQ Quota, it is assigned to Road Side Waiting List.
RL quota caters to passengers travelling from B-C-D. RL quota tickets are never available from A. When RL quota exhausts, RAC begins, and followed by RLWL. In some cases when RL Quota is small, the RLWL is active immediately. There can be more than one RLWL for some long distance trains (Rajdhani).

@Dipyaman Basu*: Re# 97391-21
Start Station: A
Destination Station: B
Station C: Sharing GEN Quota along with A (eg. NDLS [A] & GZB[C])
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Station...
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X: If Individual Remote Quota exist
RSWL: For WL from A to X
RLWL: For WL from X to B (or station between X-B)
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Station Y: Big Station, with nearby small station (Group P) sharing Quota of Y
PQWL: For WL from A/C to Y/Group P
PS: Individual Quota of Station Y can be Remote or GEN & PQ is created for all such combination of Stations as like Station Y (& clubbed as single PQ Quota for entire train's route)
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Station Z: Intermediate station having high GEN Quota from A
eg. NJP or HWH for Guwahati bound train
RLGN: For WL from Z to B or in between station (Z-B)
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PS: These WL are generally provided, when GNWL/RLGN exhausts or when RL/RS/PQ-WL is too low as compared to GNWL/RLGN. There isnt any set rule of provision of WL. RSWL/PQWL can start before GNWL getting exhausted or RLWL can start before RLGN getting exhausted.
eg.
DBRT Rajdhani (2423)
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NDLS-CNB (Remote Quota of CNB-RS): X
CNB-GHY (Remote Quota of CNB-RL):Y
CNB-DBRT (Remote Quota of CNB-RL): Z
X=Y+Z
But WL can gp criss-cross even for NDLS-CNB getting GNWL & CNB-GHY/DBRT getting RLGN!