Hi,
In UCCE deployments, there is no hard bonding of the Agents phones with the Agents unlike in UCCX (where in you have to use the specific user ID with the specific phone\DN).
IN UCCE any agent can use any extensions only thing is these phones have to controlled by CMPG application user.
Regarding the license part, i think its only the concurrent active logged agent seats which will consume the seat counts.
Hope it helps.
Anand
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