@Gregory ********
interesting… USA said three months, and Hanoi said two months. You’re right Phenom Penh doesn’t specify which could be the best route.
Last time I entered at BKK and used  “safe entry” service. They specifically asked if I had been to Cambodia in the last three months. Because I would be denied entry. A little concerned about going to Cambodia right now but maybe with the proper visa and not a “visa free” stamp I’ll have a different result