You mentioned you were still getting MSE updates earlier was it maybe them and some other odds and ends that are still around in Windows 10? They sort of combined MSE into Defender in 10 and updates for that are reasonably regular.
As the patch Tuesday stuff should be available now I'll fire up my Win10 laptop and see what I get on top of the rolling cоck ups fix.
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I get windows defender, net framework, and malicious software removal tool on top of the Win10 cumulative update. I imagine you probably got those but not the win 7 or 10 patches.