A bit late in posting, but this passed overhead yesterday morning..
https://noratlas-de-provence.com/
The itinerary says it was heading for Grenoble, but it was tracking North West. Maybe taking the scenic route up the Rhone valley then into the Isere?
A few years ago we would see a Fouga Zephyr and Douglas Skyraider flying in formation (an odd couple), but they have been absent from the skies recently.