Vinterpto - variable for current has to be after timeline?

Hi
I want to change position of actor using timeline and vinterpto node.
I need to have “current” and “target” from vinterpto node as variables.
Problem is - when I set current variable before timeline it doesn’t work, actor is not moving.
However when I set variable after timeline, everything works.

Is this a bug or that’s how this works?

I attached example screenshots, from case when this works and when it’s not.