AP FLVS Courses in the Summer

Good morning,
I was wondering as to how early one can start and AP FLVS course planned to be completed during the summer months.
Thank you!

Also, are all FLVS AP courses closed for access after the course has been completed (leaving you on your own for pre-exam studying)?

I’m not quite sure about the closing course issue but you can start anywhere from now till usually september. Then they only allow you to take the course for half credit.