They are NOT for us. They are meant for MSFT only.
Somehow, it was "exposed" to the general public. That includes build 9931, 9932 and 9933.
They won't get installed. All you'll get is an error message.
From Insider Hub.......
Windows Insiders who have installed KB3035129 may see reports in the Settings app under Update & recovery that a new preview build is available. Attempts to download the new build result in Error 0x80246017.
KB3035129 included a code change which unintentionally had the side effect of changing targeting for builds, allowing builds that are exclusive to Microsoft employees to appear available. No new builds are available which are newer than 9926 at this point. We will issue another update shortly to correct the issue and ensure that Windows Insiders are able to successfully get the next build which is made available to you. We apologize for the confusion and thank you for your continued participation and feedback.
One of the fixes is ......The Settings app incorrectly reports that new builds are available, which return error 0x80246017 when attempting to download
Finally I don't have to put up with that silly error message.