A short clip from an upcoming episode of My Little Pony: Tell Your Tale has been released on the My Little Pony: Tell Your Tale YouTube channel. Unusually, this clip has been released well in advance of the actual episode, which probably won't be out until August. It even seems to take place after My Little Pony: Make Your Mark Chapter 4. Obviously, if you don't like spoilers, please don't watch the clip or read the comments on this post.
According to the YouTube Content ID system, the episode is titled "Sparkle School" and will be the 58th episode. At time of writing, the newest episode is episode 52, so if the episodes keep being released every two weeks, it'll be August 10 before the full "Sparkle School" episode gets released.
Misty's appearance in this clip matches the way she's depicted in her "Style of the Day" toy set, where she also has a reddish mane and the same cutie mark. She also appeared with a reddish mane in a social media post from earlier this month.
Twitter: @_overcast07