Eat-Sleep-Railfanning 🔄 Repeat - Shankar Mehani

Sir,
All the replies are OK so far the individual experience and knowledge is concerned.
Typically, booking is closed before 4 hours of scheduled departure of train from the station of which quota is applicable to the boarding station. Thus, for all the trains departing from the charting station between 00:00 hrs and 12:00 hrs. the booking is closed by 20:00 hrs. on the previous day. Accordingly, Charting takes place at any time after 20:00 hrs. Normally, for the morning trains you can expect between 21:00 and 22:00 hrs. but instances are there...
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that even at 20:01, the chart is prepared for the next day morning trains. In nutshell, charting for this slot trains can be expected between 20:00 and 22:00 on the previous day.
For the next slot of 12:00 hrs. to 24:00 hrs., the booking is normally closed before 4 hrs. and thus charting may take place any time after that. Yet, sometimes the booking is kept opened even within last 4 hrs. (normally when the train is empty to some extent or for a VVIP booking) and in such cases, the charting is delayed. In this slot, I have experienced charting before (more or less) exact 4 hrs. (at 15:51 for 9132 and at 18:16 for 9116, try and experience this sometime) and also just before 55 minutes (2951 or 2956 may be tried some time where you would normally notice not before 2 hrs and sometime even not before 1 hr – this happens normally for VIP allotments).
Summarily to understand :
Departing between 00:00 Hrs. and 12:00 hrs. from charting station – between 20:00 and 22:00 hrs. of departure time, in general
Departing between 12:00 Hrs. and 24:00 hrs. from charting station – between last 3 hrs. before one hour of departure time , in general
Note: If the train is re-scheduled, the charting may (in general, is) done according to the re-scheduled time.
Thanks!