You will have an opportunity of a free upgrade to Business Class when purchasing Flex Economy ticket or above (booking class S, M, B, Y, U, Z, W).
This offer applies when members buy tickets and take one domestic flight operated by Vietnam Airlines only in some periods from now through June 30, 2020.

Please access here for more details about routings and conditions applied.

If you have already used the offer, please disregard this letter.