According to KVS, it was tech issue.
[KVS Availability Tool 7.3.4/Diamond - Operational Info: AY 69/23 Apr 2014]
Code:
Planned Flight Info
Segment Departure Arrival Duration
------- --------- --------- --------
HEL-HKG 23:40/Wed 14:30/Thu 09:50
Segment Flight Note
------- --------------------------------
HEL-HKG MEMBER OF ONEWORLD
HEL-HKG DEPARTS TERMINAL 2
HEL-HKG ARRIVES TERMINAL 1
HEL-HKG 1/ MOVIE
HEL-HKG 2/ TELEPHONE
HEL-HKG 4/ AUDIO PROGRAMMING
HEL-HKG 7/ DUTY FREE SALES
HEL-HKG 9/ NON-SMOKING
HEL-HKG 10/ SHORT FEATURE VIDEO
HEL-HKG 12/ IN-SEAT POWER SOURCE
HEL-HKG 15/ IN-SEAT VIDEO PLAYER/LIBRARY
HEL-HKG ET/ ELECTRONIC TKT CANDIDATE
Location Time Operational Event
-------- ----- ---------------------------------------
HEL 03:20 ESTIMATED TIME OF DEPARTURE
HEL DELAY AIRCRAFT DEFECTS
HEL 03:23 LEFT THE GATE
HEL 03:32 TOOK OFF
HEL 03:43 PLANE IS LATE (IN HOURS MINUTES)
HEL DELAY SPARES AND MAINTENANCE EQUIPEMENT
HKG 18:03 ESTIMATED TIME OF ARRIVAL
HKG 18:12 AIRCRAFT LANDED
HKG 18:16 ARRIVED