Actually, it’s $40,000 with financial aid. Net price = costs after scholarships and grants have been deducted. Typically you can then deduct about $2,500 thanks to work study and $5,500 from federal loans, and work over the summer for $2,000 or so.
But depending on your family’s resources, your expected contribution would be anywhere from your loan/work study/job to 65,000.
Some pay the full $65,000, others don’t, depending on parents’ income and assets.
Caltech costs even more “sticker price”. Both have generous financial aid for families earning up to 200K with appropriate assets, but no merit aid (since all admitted students are worthy of “merit” aid.)
Did you run the NPCs before you applied? What were the results and were your parents OK with them?
Brexit will not affect you since you didn’t plan to use a French address as proof of residence in the EU to get the EU rate. Furthermore, I believe that European students will be “grandfathered” and will remain at UK rates for the duration of their course (received a note to that extent).
It may affect Cambridge in that the EU gave a lot of grants and subventions for scientists and scholars.
In the UK, you would start your program from scratch. So, if you did your year in prepa, you’d start as a first-year at Cambridge. If you did the two years and failed (like 90%), you’d still be starting as a first-year.