Originally Posted by
findark
Award and cash tickets pull from different inventory, and 315 connecting to 1859 on that day is zeroed out in both cabins (J0 W0 Y0).
Delta commonly suppresses inventory on connections it doesn't like selling, and -JFK-SJU is a pretty common and extreme example (since it would cannibalize nonstop traffic to JFK). If I recall, someone posted about this exact combination before.
Yep, it's been brought up in the past. They have a handful dates that have flight pairs with married segment inventory availability in FC buckets on this routing, but they largely suppress it for most flight pairs because of noted cannibalization of more pricier fares involving the D1 seats on this routing.
I believe the award system is not as sophisticated and doesn't really employ married segment inventory in the same way and they will sell down to last seat for awards. Although it will often be in highest award bucket on more desirable routings. In this case, the 95K award level is an OJ class/CSY950 award which would be highest level. Based on OJ/OC/OD/OI/OZ award booking class hierarchy and the third letter of award fare basis code which indicates level (Y/B/M/H/Q/K/L/U/T/X/V -- borrowed from coach class hierarchy).
Allowing D1 flights on FC fares at all is an anomaly. FC fares (which have an 'F' in second to last letter of fare basis code) within US48 expressly prohibit flying D1 flights in the fare rules. There are a separate set of D1 fares (second to last letter is a 'D') on both non-stop D1 routes, and on a number of other city pairs between West Coast and East Coast, which apply when a booking includes D1 flights.