Applying for UK boarding schools (as a singaporean)

I’m a Singaporean student who has been planning to apply to boarding schools in the uk for entrance next year (2025), but I’ve missed some application deadlines 😓 I’m quite stressed thinking about the whole application process, though I really hope to get into a a school in the uk. I’m a local student in Singapore, so the school system is a slightly different as a new school year starts in January and I plan to enter in year 10.

Does anyone have any advice regarding the application process as well as some boarding schools that accept international students? What worries me the most is the fact that many top schools that I plan to apply for only accept students at certain entry points (11+, 13+ and 16+), so I’m worried they won’t be accepting students in between those points 😭 Do some schools make exceptions to offer students places in between these entry points?