Hi,
Changing the channel of an AP is not only depends on this(arm free-channelindex) criteria, it also depends on others,
1. If "client-aware" is enabled and clients are connected to AP then AP will not change it's channel.
2. AP will not change it's channel untill the "arm backoff-time" is not reached zero.
3. if all the above criteria matches, AP will wait for "arm wait-time" then chages it's channel.
Hope you understood the criteria,
Please feel free to comeback if want to know some more details about ARM :)
Cheers,
Venu Puduchery
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