If you now trade up a CAL, the current BES5 Cal will remain valid and active.
At the end of the trade-up phase, only those cals which are used on the BDS are converted to permanent CALs and, all not currently used remain active for BES v5.
I think, this is a very generous offer from RIM, because it allows you for a long time test, and, if not sucessful for all or some devices, your Licenses will remain valid for the BES v5 Platform.
As I understand it, you even might trade up only a partial amount of licenses for a given key.
This is the fine print if you trade up a CAL:
This trade-up program shall be available from January 23, 2013 through December 31, 2013, subject to extension at RIMs sole discretion, ("Program Period"). You are authorized to trade-up Your entire licensed quantity of keys associated with the BlackBerry Enterprise Server CAL keys.* To continue with the order process for the BlackBerry® Enterprise Service 10 version 10.0 (BlackBerry® Device Service and Universal Device Service) and/or BlackBerry® Enterprise Service 10 Enterprise Mobility Management Standard v10.0 for BlackBerry Client Access Licenses (CALS) (as applicable)**, that You selected at the time of order please read this Notice and click "I Agree" below. If You do not wish to continue with the order process after reading this Notice click the "I Disagree" button below.
BlackBerry Enterprise Server CALS ("BES CALS") traded will remain valid for BlackBerry OS devices until the end of the Program Period at which time You shall have acquired and activated BlackBerry 10 smartphones with BlackBerry Enterprise Service 10. Trade-up licenses issued to You are temporary licenses and valid during the Program Period ONLY and are limited to BlackBerry Enterprise Service 10 EMM Standard for BlackBerry features and capabilities. Following the Program Period BlackBerry Enterprise Service 10 EMM Standard for BlackBerry v10 CALS ("v10 CALS") will be issued to You by RIM to replace the temporary licenses corresponding to the actual quantity of BlackBerry 10 smartphones activated during the Program Period and shall not exceed the quantity of temporary licenses issued during the Program Period. Upon termination of the Program Period the BlackBerry Enterprise Server CALS which You have utilized during the Program Period will no longer be available for future use. Any unused quantities of BlackBerry Enterprise Server CALS which You have not utilized during the Program Period will continue to be available for current or future use at the end of this trade-up program. You further acknowledge and agree Your use of the new v10 CALS shall be subject to the terms and conditions of the BlackBerry Solution License Agreement ("BBSLA"), unless You have a separate agreement with RIM governing Your use of this software and the new v10 CALS. The current BBSLA can be found at BlackBerry - BlackBerry | BlackBerry.com Legal Notices from Research in Motion (RIM) - US.
* Partial trade-ups are permitted.
** This offer is NOT applicable for BlackBerry Enterprise Server Express CALS or BlackBerry Enterprise Server Trial CALS.
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