Hi @11508069
Welcome to the Microsoft Q&A Platform! Thank you for asking your question here.
Enabling automatic OS image upgrades on your scale set helps ease update management by safely and automatically upgrading the OS disk for all instances in the scale set.
Please refer to this link for more information on Set to automatic OS image upgrades-https://learn.microsoft.com/en-us/azure/virtual-machine-scale-sets/virtual-machine-scale-sets-automatic-upgrade
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