We are looking to try autopilot with Azure AD only as well as hybrid AD join. Want to understand all the licensing requirements for Azure AD, Intune and Autopilot. Is it possible to run a Autopilot in production with limited number of Azure AD Premium P1 licenses. We do not have Azure AD P1 for enterprise only few licenses .

1) Will it be possible to reclaim these Azure AD P1  licenses and assign to another set of machines after autopilot process is complete.

2) Without Azure AD PP1 what functionality do we loose with respect to Intune and autopilot in production environment.

3) Do we need to enabled Device Write back in Azure AD connect, when is it needed?