You can get teachers from the school you went to through junior year. It will just be slightly more complicated (depending on how exactly your new HS handles letters of recommendation). My advice to you – get to know your new guidance counselor ASAP after your move. You will need the current counselor to write the counselor letter for you, so you need to let him/her get to know you as well as possible. Let the new counselor know that you are going to be submitting letters from teacher from your old HS and ask what you need to do to get that to work logistically. Your counselor should be able to help you with that. (For what it’s worth, my son submitted a letter from a teacher who had been a long term sub for his junior year, and one who had taught him sophomore and junior year but then left the HS, so neither of his letters were from current teachers at the HS either. It’s doable but sometimes a touch complicated.)