Hi Bob,
you can run diff code in a mobility-Group but its not recommended.
Reason: As you know APs have to download different code on failover means AP will take around 5 minutes to download new image....
Info: The only thong you must make sure of, is that you have the high availability set on the access points. When you have different code versions running, you need to make sure AP's don't move around to the various controllers, which can cause you issues.
Regards
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