Upgrading from Original SimpliSafe to the New SimpliSafe System

I have just purchased a new SimpliSafe system to replace the original SimpliSafe system currently in use. What will I need to do to swith the account over to the new system and what, if anything, will I need to do about the professional monitoring? The monitoring is already setup with my police and fire contacts, etc. Is there something I must do when the new system is active and the old one disconnected?