Yes, that is correct. If "Auto-set from device" is enabled, the networks settings listed in that Overrides section will not be changed on the device. So the IP address you've already assigned to the APs will not change.
This is accomplished by cnMaestro reading the network settings from the device and then pushing those same settings back to the device as configuration.
If you enable Auto Sync in the AP Group, devices with "Auto-set from the device" should not have their network settings changed.