Inglés moving to Barcelona - Job market question

Hi everyone, this is my first post so please point me in the right direction if I've missed any important info :)

I'm planning to move to Barcelona early next year and I'm currently trying to understand the job market to manage my expectations when I arrive.

My career has been in digital marketing management for a professional body in the UK, ideally I would like to continue this after I move.

I currently have Spanish at around level B2, still learning and with plans to take the B2 exam in November.

My questions at the moment are:
1 - What is the supply/demand of 'English-first' management positions, against the number of applicants? I see plenty of positions on various sites, but not sure how many applications these receive?
2 - I'm currently trying to arrange appointments with recruitment agencies to coincide with a visit to Barna next month e.g. Social You. Can anyone recommend any in particular?
3 - Would a better plan be to start my search after moving to Barna? In which case, could I expect to easily find any temp work in the meantime? I'm not picky.

Thanks in advance for any guidance you can provide.

All the best

Owain