Leader Keiichiro Koyama announced on his radio show a special countdown which will appear on official JE site, which you can find here
It is the number 4-colored/ empashized countdown clock
Countdown ends April 15, 00:00JST
According to japanese fans the swf of the countdown is named "ALBUMSINGLE"
credits 1, 2
OMFG, I'm sorry if this turns out otherwise, but yeah, so we can wait together! O-M-G if this is really gonna be their comeback!