So I couldn't find anything about this "ASSUMED SOUNDS" unit. I bet it's a doujin unit considering Warner has hired doujin musicians in the past (Accel World) and has a doujin group performing the OP for this show.
Also, I've learned that Phi Brain is getting some new music for the third season. Maybe there was even new music for the second season but if there was they didn't release a second soundtrack.
Anyways, looks like 20+ tracks on that list. I hope for a release because the first soundtrack had
some interesting
music.