EDIT as of 1055GMT: The airline in late-Friday (local time) removed planned Vietnam operation in late-July 2020. Following information is based on listing on 18JUN20.
Jeju Air in late-July 2020 plans to resume service to Vietnam, scheduled from late-July 2020. Planned operation for the month of July 2020 as follows.
Seoul Incheon – Hanoi eff 24JUL20 2 weekly
Seoul Incheon – Ho Chi Minh City eff 29JUL20 2 weekly