Hi
These licences are coming from Cisco One Licensing mode and was allowing you to use Prime, ISE,…
Now you’re replacing these switches but are you using Prime, ISE ?
If so, you will need to have a license for Catalyst 9k on Prime. For ISE, C1 licenses was giving you 25 base licenses. I guess these licenses are usable with the C1 licenses purchased at the time of the Catalyst 2960x (not sure if they are still valid when you remove these switches). You can contact your Cisco representative or open a TAC case to the license team to get the right information.
Thanks
Francesco
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