Our Ha Giang, Angel and Cao Bang videos were all taken in late Feb 2023. When planning in Australia we found it difficult to determine what was the best time. Really depends on what one wants to do, for photography it's best after rain...but go in the rainy season and one is unlucky, Ban Gioc and roads will be in flood. Also it's pretty hot in a typical Vietnam summer. The Vietnamese over there say the best all round month is September. Go to Wang's facebook facebook.com/hi.hoanhtrungduong and you can see pics of the different times - he is there in Ha Giang.