Julien is from Geneva Switzerland , the city is about 300m above sea level(no altitude training there), and from December till April you have good chances of stumbling upon snow (though it depends on the years). During those months the temperatures vary from -10 to 10 (sometimes) , so if you're looking to run up to 190km per week in the cold it's quite tough...( you waste so much energy just trying to keep yourself warm).
Ah so, if you want to hit altitude resorts, basically you will only be able to do quality runs from end May till October... Making it short and concise Switzerland is good for year round ski practice, not really running.
Moving to Kenya is actually a brave and smart decision, provided you are OK with living a simpler life without the commodities of a "luxury city " like Geneva.
Looking forward to Julien's upcoming races.