11.1.12. Feature Licensing 
A license is necessary for operating a survivability unit in a OpenScape
4000 system.
All host system licenses are also used on the survivability units
in emergency mode. The survivability units are operated without licenses.
As a result, a 30-day grace period for license management begins once
a restore has been performed. All SWU features are disabled at the end
of this 30-day period.
It is advisable that an APE Backup is scheduled at least once per
month on the central system. This will not only ensure an APE restore
on the survivability unit that would reset the 30-day grace period, but
also that the database of every survivability unit is kept consistent
with the central/host system, to reflect any configuration changes.
INFO:
If the 30-day license management grace period was already active
on the central system and only 10 days of unrestricted operation remain,
then this restriction also applies to all survivability units after a
restore.