Actually it's not really weird at all, but an evolution in the workings of Windows Update. Fully automatic updates without user intervention are now a thing of the past unless someone keeps a version on their machine that is actually going out of support. Windows Update itself interrogates the actual computer it's on to determine the hardware profile, and depending on that hardware profile, it will or will not be added to an update cohort where a Feature Update is offered for the user to Download and install. There have even been instances where a Feature Update has been offered, but the offer not taken up by the end user, and it gets retracted for a time because some "late breaking problem" has been identified that was not known for that hardware profile previously.
Check for Updates as a way to force update has been eliminated, too. The only two ways I know of to force update are using the Update Assistant or the Win10 ISO file to do a feature update, neither of which is a good idea in the early days of any Feature Update release.
As has been said on many occasions, by many other than myself, best practice with regard to Feature Updates is to do an occasional check of the Windows Update pane to see if it's been offered. Then, and only then, and preferably after having done a full system image update, should the Download and install link be activated to apply the Feature Update.
Brian - Windows 10 Pro, 64-Bit, Version 2004, Build 19041
It’s hard waking up and realizing it’s not always black and white.
~ Kelley Boorn