Fire a beacon_revisited event when we get a checkin event that occurs some window of time (e.g., 60s here) after the last checkin event. Keep in mind checkin is only fired on task acknowledgement. If you set the window to 8 hours and don't interact with the Beacon for 8 hours--you'll fire revisited.

checkit.cna

global('%checkins');

on beacon_checkin {
	local('$last');

	if ($1 in %checkins) {
		$last = %checkins[$1];

		# has it been 1m since the last task acknowledgement?
		if (($3 - $last) > 60000) {
			fire_event("beacon_revisited", $1);
		}
	}

	# store last checkin
	%checkins[$1] = $3;
}

on beacon_revisited {
	println("Beacon $1 is here!");
}

Could this be extended in some way to create working hours for a beacon?