I hate you, KyoAni. I hate you.
Mio has been cloned. And aged.
In the K-ON! group’s attempt to find a mentor (after realizing that Ritsu didn’t submit the proper paperwork to the student council), they discovered that one of their kind-hearted, loving teachers was a former member of the light music club. Yes, from the same group that made death metal on that tape.
Anyways, long story short… The group is now official. Yui has someone to teach her the guitar. Tsumugi has an idol.