I've seen in Support that users often expect they will receive userpics after their Paid time, and even if volunteers explain it, sometimes they ask back because they believe they should receive more pics. Perhaps the chart on the page would make it more understandable.
I don't really know how one would word it (I no speak English!), but perhaps something simple like "If you have received Loyalty Userpics, you may wish to view your Loyalty Userpic History.", etc?