Clear Text from Keypads

This seems like a silly question, but I couldn't find the answer via searching and experimenting.
 
I have 3 M1KPNAV.  Some of my rules display text on the keypad.  However, when I clear the message from one keypad I want it to clear from all keypads.  Is this possible?  
 
I know I can set a rule to clear a previous message.  However, I don't know when to trigger this.

Great question. I use messaging on my keypads, but have never really paid specific attention to a message persisting on another keypad. We have some generic messages on ours as reminders (e.g. feed dog, take out trash) that we rarely clear anyway. Now I'm interested to see the results on my side to see if they mirror what you're seeing - I assume so.

So I think once you clear the message from one keypad it does clear from the other...just not right away.  It might just be 30 seconds, maybe 30 minutes, I don't know.
 
In my previous test I would hit clear on one and check the other right away.  The message was still there.  However, in normal practice once I clear a message the next time I go to a keypad for any reason it has been cleared.