That's how event based games work in general.
Isolated events are easy, but if you update part of a event chain, then it's a different story.
If a part of something was updated which you already finished, you won't see that, since it's already finished and has the according state. Launching that partial event again at a later state would not fit the storyline of the arc which it it is part of.
And it would also raise the problem how to proceed after that partial event. Replay the whole rest of the storyline? What about all the events that has already triggered? Replay them as well? What bugs would that cause?
I know that is how the event based games work. What I meant with this sentence is that I think dev just added event and did not consider at all how the game behave for people that are further in the story. It is his right of course and I understand it: you think of a game as a whole not a chunks. As this is kinda "early access", dev had all the right in the world to think like that. Having said that, I believe it'd be nice if dev did think of people already playing the game, especially because it does not require too much additional work (more on that in next paragraph).
If you'd read my post carefully, you'd see that I talked about event in the event chain and specifically addressed this issue! It's quite easy to do this. For example you want to add an event that only makes sense if Evelyn is not PS yet. You have three approaches:
1) To the usual trigger conditions you add a check if Evelyn is PS and if yes, you skip the new event. This is simple but has disadvantage of requiring players to start from the beginning if they wish to see new content.
2) In addition to the point 1 (which is still needed, so that you don't trigger event twice), you add trigger when going to sleep. If conditions are fulfilled and Evelyn is PS, event triggers as dream sequence which is clearly flashback. A bit more work, but the advantage is that every player will be able to see it without replying the game.
3) Sometimes it's possible to adapt an event a bit so that it's still triggering normally, but depending on the player's position in storyline it plays out differently. Of course this approach may not be possible for all events. If possible this would be the best approach. However, it's also most time consuming for the dev.