Two things to check.
1.) Make sure that all the APs are running the same version. Number matters not the name. For instance
ArubaInstant_Centaurus_8.6.0.17_83573 and
ArubaInstant_Vela_8.6.0.17_83573 will work together because they have the same
8.6.0.17_83573. If they are running the same version, they can join the same VC cluster.
2.) If Auto-Join turned on? If not, APs will not join the cluster unless it is manually added.

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Dustin Burns
Lead Mobility Engineer @Worldcom Exchange, Inc.
ACCX 1271| ACMX 509| ACSP | ACDA | MVP Guru 2022
If my post was useful accept solution and/or give kudos
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