This is now being tracked on https://status.meraki.net Current status (2:15pm pacific on 3 Sept 2024) is:
Monitoring - Our engineering teams have deployed a fix which mitigates impact to customers. Customers should once again be able to successfully update switch port configurations via the Meraki Dashboard. We will continue to monitor systems to verify correct behavior.
Please subscribe at https://status.meraki.net for further updates.
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