Long range tank - breather line versus fill line

[BigRAWesty]

I'm wondering whether LRA has done a half hearted job on mine(some twenty five years ago).
There's no "vent to atmosphere" hole/filter/valve from the tank or the fill line/quick fill line plumbing.
Only valve is the black cylindrical one in the picture, which is on the charcoal canister line which comes out of the top of the "expansion tank" on the top of the tank.

I'll take a photo of mine when home mate