KB4492978 released for version 1809 for Release preview
After releasing KB4482887 for general public last week, Microsoft is about to release a new update. This update, KB4492978 was released to Release preview ring a while ago as Microsoft does it with cumulative updates. No changelog is up there, but it is expected not to have big changes as the build number is incremented to 17763.349(just an increment of 1)
We would update the article as soon as we have new information.
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Reset Windows update in Windows 10 and earlier versions of Windows