If the first destination is Mexico City and Phil will be streaming in four hours from now, it means that the first leg will be a night leg, there is no time difference between CST & Mexico Time. Because of the live event, I dont think there will be HOO.
What if they travelled to MEX independently and we'll have TAR's first official starting line outside the US? It does not make any sense to start live event from the first check point, not from the starting line.
For some reason they didn't want to split teams into only two flights, that's why Mexico is the first destination - it's easily accessible.