In Synfig you can’t go to frames after the last frame in the scenes.
I understand from discussions and bug reports that this is a conscious choice but I would like to argue against it.
If you don’t want to end every scene with static still characters but rather with characters in motion it is much easier to animate those motions continuing past the last frame. It is much harder to animate up to one point in a motion and stop there. It’s very difficult to get a natural feel to it and the feeling that the motion continues from that point.
Also with the same argument I would like the possibility to go to frames before start of scene. To negative frame numbering. It’s much easier to start motions earlier than to animate from one point in mid-motion.