Update Tuesday yesterday only had some updates for Microsoft Office. There was also an update for Windows Defender.
Conspicuously absent is Windows 10 version 1903 which is not yet on windows update. The version of MSDN is 18362.30 so its likely that Redmond is testing this more before rolling it out generally.
This suggests Microsoft may wait until late in May before distributing the semi-annual update.
Update rollups have been delivered out of sync with Office updates etc. This suggests the update scheduling is now permanently out of band.
The MediaCreationTool1903.exe has also been yanked. This suggests that Redmond has discovered more problems. The problems with 1809 are probably the reason for the caution.
Microsoft made so many changes with 1903 compared to earlier version is the main reason for problems.
A lot of misinformed articles on the Linux Subsystem. This is for Hyper-V use which is intended to improve the performance in data centers. Many shops use Hyper-V on bare hardware and a single instance Windows Server. Then the Server manager can handle all the blades from one console. Linux is popular for web servers. Some shops may have more Microsoft servers depending on the workload.