Single (Swedish) mum, currently living in the Netherlands attempting to move to Brighton and find secondary school place son!

[NordicNoirMum]

Dear everyone on this forum!
I realise my topic overlaps somewhat with previous and recent threads so apologies for that!
I used to live in London (where I still have family) but I have been stuck in the Netherlands for 12 years now due to my son's father being Dutch. There is now an opening for my son and I to leave and I'm doing my best to research options in Brighton. My son is currently in what you'd call Year 7 (in an academically selective secondary) and I'd hope to leave so he could start Year 9 in September 2017 (yes, looking ahead!!).

I've written to 6 (secondary) schools (with Sixth Form) so far:

Blatchington Mill School and Sixth Form College
Hove Park School and Sixth Form College
Brighton Aldridge Community Academy
Portslade Aldridge Community Academy
Shoreham Academy
Steyning Grammar School (which I know is in Steyning)

I'm wondering if anybody has any thoughts/advice/opinions on or experience with any of those schools? Long waiting lists? Any good? Awful? Any other recommendations?
I would be looking to buy a 2 bed apartment and obviously need a job but as far as I can see getting a school place is the biggest hurdle and what I am most concerned with!
MANY THANKS for ANY thoughts!