I'm having the exact same issue.  My  wife got a new XPS so I dusted off her old 5558 and put an SSD in it, reformatted and seemed to get everything updated.  I had dell update installed and I think that's what was causing the once a day notification updates.  I also have supportassist installed.  With support assist when you launch it (it doesn't start on startup) it will notify you but I don't think we have the need to open that every day.  Maybe once a month or so?

Which Dell update programs do you have installed?

I know there's Dell Command but that looks similar to supportassist.

Hi docqualizer,

Thanks for posting.

Here is some information that was helpful for other users: http://dell.to/2ydVVAu