You're right John, that is a Validated(External) article that should be visible on Support (with or without a contract). I've opened a case with internal IT about it, and the KBA-4423 should be found again by tomorrow.
Here is the important details from the article Chase:
Island-NNNNNN is available on non-mesh or standalone APs. It comes up when
AP in factory default.
Or, AP cannot reach its gateway.
Island WLAN gets disabled when,
AP is no longer in factory default.
And, AP can reach its gateway.
Customers who do not like seeing an Island SSID on their Standalone AP can manually disable them.
Login to AP via SSH and issue CLI commands: set state wlan102 down set state wlan103 down
Note: The wlanXXX may be different on 64mb and 128mb RAM model Access Points. Use 'get wlanlist' to determine which wlans are available on your modle of AP.