EU/EEA immigration queue at Przemyśl Główny

I might be travelling by train between Przemyśl (Poland) and Lviv (Ukraine) in a few weeks and with quite a lot of experience with confusing and non-intuitive border checkpoints in Eastern Europe, with information often only being given in the local languages and not English, being slightly prepared would not hurt.

I've already found out that Schengen exit immigration checks are performed at the railway station in Przemyśl before boarding the train and that there are separate queues for EU/EEA and non-EU/EEA citizens, the EU/EEA queue ususally swift, while you can end up waiting for hours in the non-EU/EEA queue. The same, when coming back from Ukraine. You disembark from the train in Przemyśl and then queue up for immigration checks.

And these separate queues are also the subject of my question:

Being an EU/EEA citizen, is it obvious when I come to the station for departure or arrive back from Ukraine, where I can find the right queue? I have seen photos of endless queues in front of the station building and would greatly appreciate not by accident to line up in the wrong queue.

The photos available on Google Maps show the mandated English-language signs on the doors to the border control building, one saying "EU/EEA/CH" and the other saying "All passports." If there aren't two obvious lines for these two doors, I would walk to the building and try the door, or, if there are two obvious lines but it isn't obvious which is which, walk to the building to identify them and then walk back to the end of the EU/EEA/CH line.

The photos and some commentary indicate that the line for EU/EEA/CH passeports is on the left, but that appears to be for those entering Poland, and it is not at all clear whether the same is true for those leaving Poland.

It may be helpful to know that the Polish word for "border" is granica (the c being pronounced as ts, contrary to the expectation of many), with different endings possible as in graniczne (an adjective). This root is shared by many Slavic languages, if not all of them, and was borrowed into the Germanic languages, giving modern German Grenze, among others.