@latintrpt the antenna gain is a physical characteristic of it. If you add an antenna with a 13dB gain, but set the AP to expect a 7dB gain one, then you will potentially transmit a signal with 6dB of gain more than you are supposed to. As the Meraki WiFi6 APs broadcast at 6dB below the regulatory limit, so there is headroom for beamforming, you'd be fine (legally) as long as you don't use it.
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