BSL:
You gonna be at GVA as FO for some time (2 months, but might be a lot more). Thereafter I will find yourself in BSL in a very nice and professional pack of pilots! GVA (EZS HQ) is far away...
Upgrade is all between 6 months and xy years, depending in exprience and expansion.
Bringing a A320 rating along will make you jump in very quickly right now.
N1