I couldn't quite reproduce this behavior on my LTSC 2019 v1809 system - I guess only some LTSC systems will get them and others (like mine) won't. can you try reproducing this for v1903 or v1909 to see if the preview updates for those versions get offered?
It's my main system, nothing tinkered with, just ran WU to see if there were any new updates and there were.
I just got a CU preview for .NET 4.8 KB4562899. First time ever that i got a preview on Windows 10 and why on earth would i want a preview on my system since i'm not signed as an insider on this PC?
I completely agree with you. I am not signed up with MS as an insider, so why would I want a preview cumulative update. Sure, there is a changelog, but that doesn't mean that preview builds are considered "stable". When I worked at MS, we were taught that Beta means Broken! And a preview CU is a type of Beta. The best version of Windows 10 to implement at this time is 19041.388. Not 19041.421, 19042.388, 19042.421. With 18362 (v1903) some of us were at 18362.1002 when we wanted to transition to 18363 (v1909). This posed a problem because the enablement package was not designed to work with 18362.1002. It was meant to be used with 18362.418 (or earlier) to transition to 18363. Fortunately, a script was developed to get us back to an earlier build of 18362 so we could apply the enablement package to get to 18363. Using the script was OK, but it was an awkward method. It would have been better to not have applied so many CUs to 18362 until we got to 18362.1002. I've had to edit this post becuase 19041/2.423 has been released as a stable builid.