I cannot download 10.11.1. It's not showing up in the app store as an update. I'm currently on public version 10.11 Beta (15A278b
Hi Paul,
15A279 is Public Beta 6 and so the GM (Golden Master) would have been the logical progression for you to upgrade to from there. The GM is a release candidate - a candidate in the sense that it is hoped that the software is sufficiently stable and fully featured at this point to be classed as good enough for release.
Because it is a release candidate, there is no "update" available from Beta 6 to the GM - the GM requires a full installation, just as a release version of OS X does (that's not to say that it wipes your drive before installation - your user environment, your data, apps, etc. remain untouched). For this reason, the GM was only available in the "Purchased" section of the App Store, not the "Updates" section.
So, before you could update to 10.11.1, you would have needed to download and install the 10.11 GM. As part of the Public Beta program, you should have got an email about this a few weeks ago.
Unfortunately though, you've missed the boat for getting the GM because the program moved to offering 10.11.1 yesterday. This means that, because you don't already have the El Capitan GM installed, it's too late and you will have to wait for the final version to be released in 6 days.
Once you've installed the final release version, you'll have access to 10.11.1 through the Beta Program of course.
I hope this clarifies the situation. Sorry the news isn't better, but you don't have long to wait.
-Max