https://www.pcgamer.com/a-last-minute-bug-is-likely-why-windows-10s-spring-creators-update-isnt-out-yet/

Flickr via Andrew_Writer. Click for original.

Spring is already here, but the Spring Creators Update for Windows 10 is not, even though it was expected to release yesterday. Technically it's not delayed, because Microsoft never officially announced a release date. Unofficially however, the reason you're not seeing it yet might be because of a bug.