Well, they could have and indicator at concourse to tell passenger which side they should go for the next train, I've seen some of those in HK MTR. Or maybe they'll make the
entire Evergreen line to run on the left hand side of the track so both side of the center platform goes toward Vancouver. Something like this:
But actually, I'm more interested in the shape of the center platform. According to the plan, it will eventually become something like:
It would be almost 20 meters wide at the widest part! Oh, I almost can't wait for the PoCo extension, just to see what this funky platform look like when it is completed...