The Four new songs are... Remote Control Acute Secret Police and a mystery song that is yet to be revealed! I don't know when it will come out though..
You are correct. Only three songs. ACUTE, リモコン and 秘密警察. And, might I add, 秘密警察 is a pain in the butt to full combo...
Silly me! Here are Gameplays (No PV yet) of the new songs. https://www.youtube.com/watch?v=4XQBMCIub5s https://www.youtube.com/watch?v=qTUgvd0FnHM https://www.youtube.com/watch?v=UmMIY9NG9o0