Instrument change at the same point as key change - how to remove unwanted key signature?

Suppose I have a player holding clarinets in Bb and A.

The music for the Bb Cl is in F (concert), and when player switches to the A Cl, the key changes to D (concert).

The score, in concert pitch and galley view, looks like the first attachment.

In the part, I get a pointless key signature change to 4 flats when Dorico generates the “To Cl in A” message, as in the second attachment. Is there any way to get rid of it?


This has been discussed here
https://www.steinberg.net/forums/viewtopic.php?t=169696
and here
https://www.steinberg.net/forums/viewtopic.php?f=246&t=167956
and it looks that this is not yet implemented.

I thought I remembered some discussion on this, but for whatever reason I didn’t find those threads.

To be honest I also remembered those discussions, but they’re difficult to find because the search tool filters out “key” and “change”. I ended up searching for them in Google.

A possible solution that comes to my mind is to create a blank custom key signature, which would be an equivalent to an atonal time signature, in which the naturals are blank symbols. This might work, albeit I haven’t tried it and can bring up some spacing issues that need adjustments.