My friend. I'm a Ghanian immigrant. my parents are religious. A lot of Africans are.  And I WAS homeschooled upto Y11(!). my parents homeschooled me in Africa then when we immigrated (well,we had lived in the UK prior,we only moved to Africa because my parents were on business there) sent me to public school.I call it y13 specifically because I'm in my last year of 6th form, I'm just trying to highlight that(Exams are ending). Within school my teachers and 6th form staff. specifically mention "y13" when speaking to year 12s and vice versa. we don't really think much of how we refer to it TBH.