30 and 31 started the trend of having a full extra day between legs with short distance covered (minus a megaleg or intentional keep on racing) - TAR 30 in France, TAR 31 in Vietnam and Switzerland, so I wouldn't be surprised at:
Leg 1 - July 15 - Bangkok, Vietnam
Leg 2 - July 17 - somewhere in Thailand or Vietnam
Leg 3 - July 19 - Can Tho, Vietnam
The most common way to get to Can Tho and areas surrounding it is over land (they visited Cai Be on the other side of the Mekong in TAR 3 by taxi and in TAR 15 by bus), but I suspect they might be force teams to fly to Can Tho instead, allowing Phil to get ahead of the teams on July 18th by flying to Ho Chi Minh City.