Hi all, I wanted all of your input on something that has been on my mind lately. One of my letter of rec writers is my undergrad research mentor of 3 years, who just started at a different institution this fall and is an assistant professor there. She was a postdoc when she trained me but since she has professorship now I thought it would be acceptable to ask her for a letter instead of the PI, who did know me but I didn't directly work with him. Is it ok that I asked a just-promoted assistant professor instead of an tenured professor?
From what I'm reading here, it's not uncommon for new faculty to write letters for grad school bound undergrads..
My other to letters will be from my academic advisor and an associate professor whose lab I worked in during a summer internship.