Dorico 3.1 Options for Choral Voices by Section?

Does Dorico 3.1 have section-specific choral voice options? I frequently use “Sustain Ah”, but find that the program plays all four sounds (bass, tenor, alto, and soprano), based simply, it seems, on whether the pitch being played is in the RANGE of each part or not.

But when an arrangement calls for sopranos only on a Middle C, for example, the Sustain Ah sound uses all four parts (since all four parts in a choir can reach the Middle C). So the timbre suffers significantly.

If they can do them together, can’t they do them separately, with each voice on its own part?

Am I missing something here?

Dorico 3 uses the Soundiron Olympus Choir Micro sounds by default, and to my recollection it does not contain individual patches for each voice part, instead providing mixed male and female patches. You should be able to fiddle with the controls in the HSSE window to change the note at which the male voices start to be mixed in with the female voices, as described on page 6 of the linked documentation.