Hello @Azure Security,
welcome to this moderated Azure community forum.
I have not seen many problems with outputting IoT messages to blob storage.
The Azure Blob storage should be capable of coping with AIC messages even with larger numbers.
Are the IoT Central and Blob storage created in the same region? Did you specify certain properties on the blob storage? Did you specify an alternative path pattern for the export?
If this issue continues, I suggest submitting a support ticket.
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