You can have only one active application at a time.
What people don't seem to understand is that the contract changes, big time, in money, conditions, roster, part time, pension, in EVERYTHING, from one country to another.
It is like working for different companies.
Just money wise we are talking of THOUSANDS of euros of difference per month from one place to another.
Easyjet Uk is the AOC under which at the moment all the bases out of Switzerland operate. That does not mean that the work contract is the same. Germany, Italy, France, UK, Spain and Portugal have different contract for crews. Even FTL slightly change.
Easy Swiss is the AOC under which all the swiss registered planes based out of Basel and Geneva operate.
Being applicable only to one country there is only one work contract applicable.