http://worldsfinestonline.tumblr.com/post/24203585455/images-from-young-justice-bloodlines-to-be

Totally Heatwave. And Gar looks ticked off at Impulse. Maybe Impulse said something bad?

http://www.youtube.com/watch?v=wg981zg-g-k

So, they're keeping Impulse's origin as a time traveler, so it seems!

UPDATE:

http://www.youtube.com/watch?v=R3FQWB2-rtU

This isn't Bart's first animated appearance!