On the advice of other people who've successfully sold self-published stories, I'm going to stop doing the "free every Saturday" thing. You get a limited number of free promotion days and apparently they work better if done consecutively.
So I'm going to switch over to doing a weekend (Sat-Sun) free, followed by a long weekend (Fri-Sun) free.
Just don't want anyone to be surprised.
At least, not by policy changes. :)