When is a good time to come out?

I’m 15, and the school year is wrapping up soon. I’ll be starting T two months before the end of the year. I’ve heard mixed bags on whether any noticeable changes will happen then, but the big question is when to do it:

-Right after starting T

-near the end of school

-beginning of break

-somewhere middle of break

-right before new school year

-into new school year

My friends will be all chill, but it’s general classmates I’m worried about