License is perpetual and does not expire.
Support follows the agreement from DS-Manager
Included in the purchase you get full support for the DSOF add-on, following the maintenance period of DS-Manager.
Support includes all that you need to keep it running; Support via Telephone, email and remote support sessions from our MCSE certified techniciens.
Note: Since DSOF is a feature in DS-Manager it follows the maintenance period of that. If you purchase DSOF after your maintenance has expired on the main product (DSM) this feature will active without problems. But the DSOF license does NOT grant you upgrade entitlement for the DS-Manager product as well. It only grants you technical support for DSOF feature.