Teen Dependent Who Will Turn 18 / Question

My wife and I are both teachers and it appears that we can get work permits. Here is the question. My son turns 18 in late July. Is it crucial that we get work permits/start work prior to his turning 18 (hence health coverage/ right to stay in UK for one year etc) or would age 18 negate his dependency status anyway?We are both worried about this and have not been able to sort it out from available information. Any info would be greatly appreciated.

Nicholas/ Stefanie /Philadelphia

My wife and I are both teachers and it appears that we can get work permits. Here is the question. My son turns 18 in late July. Is it crucial that we get work permits/start work prior to his turning 18 (hence health coverage/ right to stay in UK for one year etc) or would age 18 negate his dependency status anyway?We are both worried about this and have not been able to sort it out from available information. Any info would be greatly appreciated.

Nicholas/ Stefanie /Philadelphia

Is he still living with you and dependeant upon you?

My 18 year-old moved here with us (although we did apply for his visa while he was still 17 and a senior in high school) he is considered dependent on us because he is in school full-time here (and while he lives in student housing, I think they believe he is living here with us? They never asked, and we never offered so I don't know if that would change things or not) but because he is a student and we are paying for his school etc. then he was good to go.