The only thing to be careful of is: which Thursday of September?

If it's the Jeûne Genevois, lots of locals will be off Thursday and take Friday off to enjoy a long weekend abroad somewhere in Europe so the airport might be busy September 7/8. Of course it's only the "Genevois" but lots of French and Swiss from state of Vaud work in Geneva and will also be off (I will enjoy my 4 days off for sure).
Just something to keep in mind and not arrive just 60min before your flight