Oil seperator removal vent line question

[ernaldamerican]

I am 99% done with the removal of the OSV. My question is the vent line that goes from top of OSV up to intake manifold. There is a second line that T's off this line up at the intake manifold. How does that line come off? It has ridges on opposite sides, and those ridges I thought pushed in. They appear to part of the T fitting, and not the removable hose.

90 degrees from these ridges are what looks to be small tabs.

My question (although sounds dumb) is how does this line come off? Do you have to press in on the tabs up or down or in to remove? i have attached a picture thanks