My guess is that reason for cutting three flights (HEL-ICN June 12, 13 and 19) is due to lack of aircraft. OH-LQF is under maintenance at SIN and it seems to be delayed. Aircfaft was supposed return back to service at 11th June. New time for return is now scheduled to 23th June.

They cut also HKG extra flights 61/62 and DEL before 23th June.

This is pure speculation without any official info.