2Do not automatically choose “SKM” — check the actual connection
Jakdojade shows the available routes. For this search it suggested a PR train. PR is the label used here for POLREGIO, so this particular journey is not an SKM train.
That can be a good thing. In our example, the 09:45 POLREGIO service reaches Sopot at 09:57 — about 12 minutes — because it makes fewer stops than the usual all-stations SKM pattern.
For this particular train, the intermediate city stops are Gdańsk Wrzeszcz and Gdańsk Oliwa. It skips stations such as Gdańsk Stocznia, Politechnika, Zaspa, Przymorze-Uniwersytet, Żabianka-AWFiS and Sopot Wyścigi.
Use the route, not the logo: if you are travelling between the main stations, a POLREGIO service may be faster. If you need one of the smaller intermediate stops, SKM may be the better choice.