There was a version of cnArcher that would allow you to specify cnMaestro Server URL and Credentials but you could specify to not write that information to the SM. The SM in our case needs to get the private IP address that will be supplied from the AP. cnArcher then needs to be able to connect to the Public IP address for the cnMaestro server to finish onboarding.
With the current version of cnArcher if you specify On Premises cnMaestro URL it writes that to the SM.
We are working on a new version cross-platform version of cnArcher. A beta version with PMP support will be available by mid August with this capability.With this cross-platform app, both Android and iOS versions will have the same functionality.