Have you tried this process. Host the IAP file (replace with the one you want) on a tftp server and run the following:
ap convert add ap-name <ap-name>
ap convert active specific-aps server tftp <Server IP> ArubaInstant_Hercules_8.6.0.7_78215 no-pre-validation
Pretty sure this takes around 10-15 minutes, and if it is in your central inventory and assigned a license, it should automatically come up in central.
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Dustin Burns
Lead Mobility Engineer @Worldcom Exchange, Inc.
ACCX 1271| ACMX 509| ACSP | ACDA | MVP Guru 2022-2023
If my post was useful accept solution and/or give kudos
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