How to force page turns for printing parts (but with gnat sized bug)
User Tip: To Force page turn, insert clef and key signature with visibility never at end of bar before page turn; force system break and exclude from bar count; insert whole rest with visibility never; insert new bar with visibility never and force system break; insert clef and key signature with default visibility.
This leaves an empty staff at the bottom of the page which players will ignore, or which can be used for text instructions or messages to the players.
The wrong measure number that appears at the beginning of the the empty staff appears to be a bug.