Remapping
Applying Time-Remapping
Turning on Enable Time-Remapping will make a new Time Remap parameter appear. By selecting it and switching to the Graph Editor, you can see a curve appear, which is linear at first.

When this option is active, the range of the layer on which it is applied is used to define the vertical scale, on the left of the Graph Editor.
If the layer does not have a range, then the composition duration will be used - here it is 30 seconds. This is the reason why this curve, which right now is linear, evolves from 0.0 to 30.0.
For the moment, this option does not change the time. Time elapses linearly over a period of 30 seconds. Note that the first keyframe is positioned at 0:0 and the last keyframe at 30:30.
Bending time
The tangents of these two points can be used to curve the line.

If we draw a vertical line at the 7th second and go down the curve, going to the left, we can make this time correspond to 10 seconds.
This speeds up the time to make the state of the layer at the tenth second much earlier in time.
Back in time
By adding points on the curve and adjusting the tangents, it is even possible to go back in time.
