Hi,
I tested this in my home lab for you Daniel.
In my home lab i have a AP22 setup with cloud management. I put a firewall rule on my Fortigate and blocked the AP from talking to the internet. I then rebooted the AP. After several minutes the SSIDs appear while the AP is still down in the cloud portal and all internet traffic is blocked.
It seems the AP does keep a local config. I imagine however that you need to get an IP address via DHCP before it starts to broadcast (i can test this too later). So if you want to use it for a survey you'd need a small SOHO router + POE injector so that the AP can get an IP (or maybe it'll broadcast without an IP?).
Hope this helps
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_ELiasz
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