[SCHEDULER] clarify idle state and stateful option

Author: alli83

scheduler.rst

@@ -336,13 +336,18 @@ recurring messages. You can narrow down the list to a specific schedule:
 Efficient management with Symfony Scheduler
 -------------------------------------------
 
-If a worker becomes idle, the recurring messages won't be generated (because they
-are created on-the-fly by the scheduler transport).
+When a worker is restarted or undergoes shutdown for a period, the Scheduler transport won't be able to generate the messages (because they are created on-the-fly by the scheduler transport).
+This implies that any messages scheduled to be sent during the worker's inactive period are not sent, and the Scheduler will lose track of the last processed message.
+Upon restart, it will recalculate the messages to be generated from that point onward.
+
+To illustrate, consider a recurring message set to be sent every 3 days.
+If a worker is restarted on day 2, the message will be sent 3 days from the restart, on day 5.
+
+While this behavior may not necessarily pose a problem, there is a possibility that it may not align with what you are seeking.
 
 That's why the scheduler allows to remember the last execution date of a message
 via the ``stateful`` option (and the :doc:`Cache component </components/cache>`).
-This way, when it wakes up again, it looks at all the dates and can catch up on
-what it missed::
+This allows the system to retain the state of the schedule, ensuring that when a worker is restarted, it resumes from the point it left off.::
 
     // src/Scheduler/MyScheduleProvider.php
     namespace App\Scheduler;