unitycoder
beta is available in the unity hub before website
seems that they adjusted hub to get install location before website..
Unity 2023.2.0 Beta 16 is now available in the Unity Hub. Installers and release notes will soon be available at: https://unity.com/releases/editor/beta/2023.2.0b16
https://forum.unity.com/threads/2023-2-pre-release-guidelines-announcements.1409883/#post-9446987
*maybe releases are coming from https://public-cdn.cloud.unity3d.com/hub/prod/releases-win32.json
doesn't contains latest immediately https://unity.com/releases/editor/releases.xml
someone has hidden knowledge, b14 and b15 already available (website shows b13 only) https://forum.unity.com/threads/the-unity6-splash-screen.1558583/page-2#post-9763870
from Hub sources can see that graphql can be used to query, also here: https://github.com/Larusso/unity-version-manager/blob/master/uvm_live_platform/src/api/list_versions.rs#L63
ok, using google site search for docs, look for "built from" string to reveal hash codes at the bottom https://www.google.com/search?q=site%3Ahttps%3A%2F%2Fdocs.unity3d.com%2F6000.0+%22built+from+6000.0%22
then plug hash code into *but not all hashcodes are available as builds: https://beta.unity3d.com/download/HASHCODE/download.html
release api *but doesn't show very latest ones (that are visible in hidden beta page) https://services.docs.unity.com/release/v1/
this is now available https://github.com/unitycoder/UnityLauncherPro/releases