According to the official website, the episodes 11 and 12 of Mahou Shoujo Madoka★Magica will be aired on April 21st.
MBS: Apr 21st 26:40 – 27:40 JST (Episodes 11 & 12)
TBS: Apr 21st 27:00 – 28:30 JST (Episodes 10 – 12)
CBC: Apr 24th 26:45 – 28:15 JST (Episodes 10 – 12)
Source: Madoka Magica official website
