@kazuya kurosawa Thanks for reaching out.
The reason for these restrictions is to prevent excessive start and stop operations that can cause instability and affect the performance of the service. When you start or stop an instance, it takes some time for the system to complete the operation and update the status of the instance. If you try to start or stop the instance again before the previous operation is completed, it can cause conflicts and instability in the system. Therefore, to ensure the stability and performance of the service, there is a minimum waiting time of 30 minutes between start and stop operations. There are internal architecture/design/performance/dependent on different azure resources that leads to this limitation.
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