According to KA's
press release, the schedule for flights starting 11/2012 is:
HKG-CCU 2050-2325
CCU-HKG 0010-0600
The same schedule is shown on third party booking sites and can be booked through 3/2013, so it is official..
But this means 5:05 hrs for HKG-CCU, and only 3:20 hrs for CCU-HKG. For comparison, DAC (nearby) is ~4 hrs each way.
Did they miscalculate because they didn't realize India has a half-hour time zone? And if so, how will they fix it? The 0010 departure from CCU means a 30 min change will change not merely the time but also the date!