San Diego is 14 hours behind Ho Chi Minh City
There is no standard 8-to-6 overlap. Someone joins early or late.
Ho Chi Minh City and San Diego are too far apart in time (14 hours) for their workdays to line up during regular hours. For anything urgent, agree on an early-morning or late-night bridge hour in advance so nobody's caught off guard. Just remember San Diego changes its clocks for daylight saving and Ho Chi Minh City doesn't, so confirm the overlap whenever the seasons turn.