Accents on empty noteheads jumping around randomly when re-opening a project

I am using empty noteheads witht he “3 spaces as a notehead”-trick.
By default, the accents on these are pretty inconsistent, but even after adjusting them manually, when reopening a project, they randomly jump around again.

Here’s what I achieved with manual spacing in a violin part some days ago (I know it’s not perfect engraving, but it was consistent):

Here’s how it looked like today after opening the project:

… and after directly closing the project (no edits, no save), and opening again:

so you can see, the issue appears to be random. Sadly, I noticed it after I sent a badly engraved score (which I thought I took care of) to my musicians…

Can you provide a minimal project that would allow us to investigate the issue? Just the passage shown in your pictures here should be sufficient.

thanks for your reply!
Here’s the file:
jumping accents.dorico (957.5 KB)