Yes, the Land-Hutcherson quintet (with Joe Chambers) opened for Miles at both concerts.
And while this happened at Antibes/Juan les Pins, the Cecil Taylor Unit (with Jimmy Lyons, Sam Rivers, Andrew Cyrille) was settling at the nearby Maeght foundation for the concerts which were held right after the Antibes ones. I was commuting from one place to the other daily.
A very busy jazz week!