What semi-annuall update channel you set? Targetted or not? I do not know exactly but I guess that MS on target channel records failed updates together with W(in)er(rror or )fault report sent by comp and does not force new update until... ????
I'm not sure about what you're asking, regarding update channel or targetting, i wasn't even aware these are options. I just check for updates every time I'm on my machine.