[MU4 Issue] Weird stem flips around the middle line

[mike-spa]

Maybe I'm just not understanding the rule causing the flip, but it feels odd.

To Reproduce

1. Note insert by mouse click
2. First note: stem down (Pic 1)
3. Second note: stem down (Pic 2)
4. Third note (A): stem down (Pic 3)
5. Fourth note (A): causes stem flip (Pic 4)
6. Cancel the last note: stems remain up (Pic 5)
7. All next B notes remain with stem up (Pic 6)
8. Move the last note up to C# by upward arrow key: makes them flip down (Pic 7)
9. Move the C# down: now all are down but the last one is up (Pic 8)

Expected behavior (I put question marks because I'm unsure)
4. Why does only the second A cause the flip and not the first one?
6. Canceling the last note (which caused the stem flip) should undo the stem flip?
7. If I continue inputting a series of B notes (I could see this happen if this was a drum line, for instance), do we really want them all with stem up? Isn't it unusual?
9. This gets corrected as soon as a note is inserted in the next bar, but what if this is the last bar of the piece?

My feeling is that some checks are missing to restore the previous positions if the move that triggers the flip is undone (either by cancelling or by Ctrl+Z).

Screenshots
If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: Windows 10