I'm looking to intern at a different place this year, and the new place wants to contact my past internship to ask about my performance. Should I email my past supervisor and let them know that they might be contacted? I'm a bit worried about getting a bad reference because they might want me back this year although I was noncommittal last year about coming back.
I think it's better to warn them but I don't know how to properly email them as I'm basically saying 'hey I'm not coming back so please say good things about me to the place I actually want to work at'.