Why are there 12 Free Champions this week?

There are 12 Free Champions listed this week on Riot's page (still only 10 pictures shown). I believe that there were 12 last week as well. Yasuo and Riven's pictures are not included either time, but they have been available in champ select (last week and this week).

A friend of mine who is new to league was really confused about how free champion rotations worked, and showed me this, and I realized something must be wrong on Riot's side or maybe Riven and Yasuo are just permanently available? That wouldn't make much sense, but it's possible.

Anyone else have any info that might help?