Do you need ESW/UCSS to convert Unused DLU's to CUCM 9.1?
if you are upleveling for the promo it would be considered uncovered. If you are just doing a straight upgrade, you can use the DLU folowing the standard transition rules and will need to purchase ESW and UCSS for the additional users.
You get Enhanced UCLs against unused DLUs (if you want). You don't need to pay for ESW/UCSS at the time of upgrade but you will have to purchase UCSS/ESW for these Enhanced UCLs at the point of following ESW/UCSS renewal. See the slide below
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