Steps to reproduce:

1. Download and import attached project.
2. Open scene: main
3. Select and simulate particle system in editor.
4. Notice that particle is not square.

Expected result: Particle should go from small square till big square.
Actual result: Size over lifetime on curves works well with x axis, but it does not work at all with y and z. (y and z are at their start size)

Note: same with both billboards and meshes.

Reproduced on 5.4.0b7