Set play rate seems not working for timeline finished ?

I use a timeline to change the value of my material parameter, and for each different material i set a specific play rate to control the speed. It works fine for the Upade, but not work for the Finished. The Finished always triggers as the timeline reaches the origin last key frame(1,1).

I wonder that it’s a Bug or the function is just what you guys expected.

Same here. It seems like a bug, ti will be great if someone can confirm it.