If you’ve arrived at platform 1 in free roam and are off, looking for collectibles, have trains arrive at another platform instead of waiting for you at the previous signal, as long as the track allows it. We do get platform alterations occasionally.
I'm pretty sure that would be a nightmare to code into timetable mode (free roam doesn't have AI trains). Plus we have Scenario Creator & Free Roam where you can do that at your own pace