CX751 BKK-DEL is now sold as 3-class daily 5/16-10/29.
The aircraft generally (always?) has F seats but has been sold as 2-class in the recent past with the F section closed or offered to elites/full-fare J pax with business service. This is a recent change as when I booked a July ticket back in February F was unavailable but I was able to change the ticket today.