Hartman has basically been swapped out for Pyne. It doesn't really change the depth chart much.
Buchner should stay unless he gets passed by Angeli or Minchey (very unlikely for 2023). Buchner will also have his degree by the end of next year. That's when he should make his decision about going or staying.
If Angeli gets passed by Minchey this Spring, then he probably should bail. If that does happen, it's not a bad thing. It just means Minchey is as good as advertised.
Regardless, I don't think Hartman's transfer affects their decisions. It affected Pyne's place in the top 2, which is why he left.