Showing instrument staves through instrument reset

This is more a report than a question: I have here clarinets in A, B, C (3 instruments per player), but in the imported xml file only the B ones were showing - including in galley view, and when the layout is showing all staves.
It was corrected by changing an instruments into the same instrument (A changes to A), and it seemed that it resetted it, so that it made the staves show again.

Yes, this is a known issue when importing a MusicXML file into an existing project: any instruments that have no music don’t get the necessary voices created for them in the destination project, so they don’t appear. I seem to remember that I have already fixed this problem since Dorico 3.5.10 was released, but I’m afraid it’ll be a while before a version with this fix is available.