Hello,
What firmware version do the AP-635s have in Aruba Central?
I understand that it will be one of these versions that I put in the table, but it is just to check.

Here are the minimum versions of the operating system:

So with iPad 12.1 you shouldn't have any versioning problems.
As a side note and if you are considering upgrading iOS versions, please note: iOS 15.0 and iOS 15.1 are not supported due to a bug in iOS, which was fixed by Apple in iOS 15.2.
Best Regards
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Daniel Ruiz
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Any opinions expressed here are solely my own and not necessarily that of Hewlett Packard Enterprise or Aruba Networks.
If you have urgent issues, always contact your Aruba partner, distributor, or Aruba TAC Support.
Check
https://www.arubanetworks.com/support-services/contact-support/ for how to contact Aruba TAC.
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