It's not as simple as "let's double the channel width then reduce the number of APs". There is a balance in how many APs you can have in one area, the AP power, used channels, number of clients, type of clients. If you are at the point where you need to go to the AP535 in order to go over 256 associations per radio, you are likely to have an RF design issue anyway.
Without understanding your environment, it is nearly impossible to get to a proper design. Classrooms for 30 students are not so much a challenge as a lecture hall with 5000 seats all occupied with students using a laptop and mobile device or stadium deployments.
What is in that VRD still most of it is valid with 802.11ax unless you control all clients and are sure they are 11ax compliant and can benefit from the 11ax features (unfortunately that are two different things). It may make sense to reach out to your local Aruba team or Aruba partner if you work through them.
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Herman Robers
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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. Any opinions expressed here are solely my own and not necessarily that of Hewlett Packard Enterprise or Aruba Networks.
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