UPDATE Nov 14th, 2018 – Windows 10 1809 and Windows Server 2019 are available again – https://t.co/NvLFSII9fM
Just few days after the release of Windows 10 1809 and Windows Server 2019, Microsoft has pulled out these releases from MSDN (and possibly Volume license) as well as paused the delivery through Windows Update.
This follows reports of missing files and Microsoft is investigating (limited details available here https://support.microsoft.com/en-us/help/4464619/windows-10-update-history)