Pleasure.
Whenever you go for any bookings, kindly cross-check between every possible journey legs. (Also against the ARP status between 00:30-8:00 hours) to know the actual number of available berths and the WL'ed status.
For example start-end would be issued against GNWL. In specific cases, where PQWL has availability, you may also get confirmed berths against PQWL.
Say a train is travelling from A-B-C-D-E-F.
If A-F is GNWL, check for A-D/A-E. If they are same, they would also come under GNWL. Else mostly they would come under RSWL. Now is most of the trains RS may not be present. In such cases they would come under PQWL.
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How to differentiate? One trick is to check the WL'ed status. RS/RL Quota have low available berths and hence WL'ed status would also be low. On the other hand PQWL is a start-end quota and hence would support high no. of confirmed berths and Waitlisted number.
PQ would not have RAC whereas RS/RL may have RAC. (Depends on how much berths it has been allotted - If it is more it would support RAC, else would directly move into WL)
A-B/C would mostly come under PQ. (Divide the entire stations covered into equal parts. RS would apply for a larger interval. Other start-intermediate would come under PQ). If A-B/C comes under PQ, there is high chance that B-C till D-E-F would also come under PQ. Again check for the status and compare the confirmed berths/wl'ed number.
For some trains covering important stations like HWH/SDAH/Delhi/Mumbai and so on, even if these stations falls in between, depending upon the demand and importance of train, start-intermediate, stations enroute between these two till the above mentioned important stations may also be covered under GNWL. Again the trick is to cross check the availability status.
For stations where trains stop for a larger time, say C/D, C/D-E/F would mostly come under RL. Now C/D would have separate charting of its own.