The following is found on page 78 (2nd column) in the 2019 NFHS Redding Study Guide:
If the 40-second count is interrupted for reasons beyond the control of the officials or the play-clock operator (e.g., clock malfunction), the referee shall stop the game clock and signal that the play clock should be re-set at 25 seconds and started immediately (3-2-4b2).
If the 40-second clock is running and the ball is not properly positioned to be snapped after 15 seconds into the count, the referee shall stop the game clock and signal for the play clock to be set at 25 seconds (3-2-4b3).
Neither rule reference is applicable to the play clock. Looking for guidance on how each of these situations are handled and the applicable rule reference(s). I don't have my new book yet - appreciate your feedback.