Effectiveness of Masters abroad for language learning

Hi guys, 

I am an undergrad from the UK attending a UK university. I am considering doing a master's degree (taught in English) in continental Europe (HEC, ETH, Bocconi etc). In addition to some of these universities being the best in the world in specific fields with world-class degree courses, one draw is the opportunity to build an additional language. Many of these universities offer intensive language courses before joining and throughout one's time there.

My question is: Do you think that through these intensive courses and a year spent in the country, I could get to a level of professional proficiency (C1/C2)?

For context, I last did French during my GCSEs (aged 15/16), I plan on working in London, and I am primarily interested in having an additional language for career purposes.

Many thanks