How do you turn on "show pre-release updates" in yosemite?
@Marksorry I can't comment your question directly, since I'd need 50 reputation to do so.For your question: Wen you quit your subscription for the seeds you basically uninstall a program on your Mac. You can re-download that program directly from Apple and install it. Since the Beta-Progamm is linked to your Apple-ID you have to log in with it. Once you downloaded that file (YosemiteBetaAccessUtility.dmg) you simply install it and you have access for the Pre-Release Updates again. Just open Appstore and install the updates.I found the file with the following steps:


Go to appleseed.apple.com
Click "first steps with OS X Yosemite Beta"
Scroll down the site till you find the button where you can download the Beta Access Utility.
Download and install
Restart if needed and it's finished