>> - Configuration profiles cannot be installed, and the device cannot enroll into mobile device management (MDM), while Lockdown Mode is turned on.

> HMM ... there are hardening settings only available through Configurator or MDM profiles. Will those be defaulted on as well?

Reading between the lines here - on lockdown mode, you can't install a profile, or enroll in MDM. What it doesn't say, is that you can't enable lockdown mode with a profile installed, or if enrolled in MDM.

I take this to mean, with lockdown turned on, I can't install profiles or enroll in MDM (but presumably could uninstall profiles or unenroll from MDM).