gosrox Stephan-P You have a misunderstanding about how the releases work. You think the release announcement means that the release is in the Stable channel when it doesn't. The releases page a listing of which releases are in which channel and the update client is also a reliable way to check. There's no delay between a release being pushed out through a channel and it being available to the update client. It's a misconception you've developed based on thinking that our production releases immediately go to Stable. Each production release goes to Alpha, then Beta and finally Stable. We do not have separate Alpha and Beta releases. Those channels are simply a way to get the production releases earlier. The releases may have issues caught in testing leading to the release being cancelled and replaced. It's very rare for us to cancel a release but it does happen, and part of the reason it's rare is because there isn't enough public testing and reporting.
Please read https://grapheneos.org/releases#about-the-releases and https://grapheneos.org/usage#updates. If you want to see what's in the Stable and Beta channels, you can see that on the releases page. The release announcements do not indicate something is in the Stable channels.