Turbo Intake Piping Missing A Vacuum Hose

[IM-32-FK]

I bought a r34 rb25det neo a few weeks ago and only today i noticed that on the blow of valve piping(about one inch thick) there is a nipple that has no vacuum hose connected. The nipple is on the BOV piping just before it connects to the turbo air intake piping(the piping with the pod filter that goes to the mouth of the turbo). Anyone has any idea where it should be connected to? here is the picture:

[Dose Pipe Sutututu]

Just block it off, I'm pretty sure it's the bleed return from the OEM boost controller.