Okay, but the tenant admin doesn't have certain privileges that the host admin does.
I always get 2 admin users, one with Tenant ID == null, one with Tenant ID == 1. The Angular UI code suggests TenantID > 0 is what makes something multi-tenant. I can only login with the multi-tenant version of 'admin' (email address = [email protected], and TenantID == 1), but not host admin.