Dorico doesn't add new pages

When I’m adding music to a Flow that isn’t the last one, sometimes Dorico doesn’t ‘reflow’ the music that follows it, and the final flow is ‘cut off’, where its music should have been pushed onto new pages.
Closing and re-opening the document fixes it.

Is this a known issue?

Not specifically, no. If you have a project that reproduces this problem, please let me know.