>> Dredging up more from my memory…
>> Or down the St Jean du Alpes valley then right over towards Chatel (can’t remember the name though)?
Col du Corbier?
As goldenwonder says the Etape does finish in Morzine on the 10th July. It goes over The Ramaz, down to Taninges, along to Samoens and over the Col du Joux Plane, finishing in the center of Morzine outside the tourist office. Deffo avoid these on that day. There are 15000 riders in the etape.
Some route ideas in this which you can pick up a paper copy in the Morzine tourist office usually
Morzine-Road-Cycling-Guide
Most Cols as mentioned above covered here, some of my actual rides which should downloadable for editing and using on a Garmin or similar:
Avoriaz via Col de la Joux Verte
Col du Corbier, Col du Grand Teillet, Col de la Ramez
Col du Corbier loop
Col des Gets, Cirque de Fer de Cheval, Col du Joux Plane
Col du Ramaz loop
Col du Corbier, Évian-les-Bains, Thonon-les-Bains loop