Thanks for observing the feature.
.
As surmised earlier in this blog, the dates are calculated criss-cross.
If you enter "Latest Departure Date", then you can click on "Calc Earliest Booking Date", and the "Earliest Booking Date" box is filled in.
If...
more... you enter "Earliest Booking Date", and click on "Calc Latest Departure Date", then the "Latest Departure Date" is filled in.
(Pl. note that "Latest" here means the Last Possible Departure Date for the given Train/Station for which ticket can be booked on the given "Booking Date").
.
Pl. note that If no date is entered on any of the boxes, then "Today" is assumed. For example, if you just click on "Calc Earliest Booking Date", then it is assumed that you wish to depart Today. So "Earliest Booking Date" for ARP 60 will be 2 months prior to today. (in December 2013).
.
The Train & Station details are useful when the train does not depart Daily. For example, say you are booking today on 12908/Maharashtra Sampark Kranti from NZM to Mumbai. The train departs from NZM only on Monday & Thursday. 60 day ARP if booked today is Apr 4 which is Friday. Since the train does not depart on Friday, the "Latest Departure Date" will be Apr 3 (Thursday) which is 59 days from today. But if you were booking from Kota to BDTS, then it will be Apr 4, since the train departs from Kota on Tuesday & Friday (+1 day) which is exactly 60 days from today.
.
Note that the same ARP 60 days is assumed for both originating station & intermediate halts. Pl. do inform if the ARP 60 applies only to originating stations and if intermediate halts get an extra day or two if the station is arrived after 1-2 days. Thanks.
