SSIDs (and aliases) can be tested on one band only. This means that sensors will only connect to the SSID and test it on the specified band. An SSID can be locked to 2.4 GHz only, 5 GHz only, or set to “Auto”. In Auto mode, which remains the default setting, the sensor will choose the best band to connect to similar to a regular client.
This can be found under the Advanced section on the Edit SSID modal.