@Nayah Felicia Welcome to Microsoft Q&A Forum, Thank you for posting you for posting your query here!
Will this impact us in anyway? is this something we will need to deal with when the diagnostic settings storage retention expires on 30 September 2025
Yes, this means we have to configure the LCM policy to delete the older logs from $logs. At the moment LCM doesn't support $logs container
Migrate to Azure Storage lifecycle management from diagnostic settings storage retention 2025
Configure a lifecycle management policy
The diagnostic settings storage retention feature of Azure Monitor will be retired and retention will no longer be applied to logs sent to storage account destinations via diagnostic settings.
It refers to the diagnostic setting of all the logging resource (not just the enabled resource). When we select Archive to a storage account, the Retention (days) will be the retention feature of diagnostic setting. As the note explained, it can be set from 1 to 365 days. if it set to 0 means it retains data forever.
If you have any additional questions or need further clarification, please let me know.
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