There's two things that could be going on. First, the upvote is adjusted based on posting frequency to keep your weekly total reward fairly constant, and you've been a bit more prolific lately. Second, I know that the powers that be were on vacation recently, have had a new kid, and have only recently started automating enrollment; so there can be a pretty hefty delay until the shares go active.

And, as always, don't thank me, thank the RNG.