Do you know how to step into functions in the debugger? It’s like the little arrow that’s pointing at a dot in the debug buttons or f11. You can try stepping into VInterpTo.
The only things that should be causing it to jump all the way to the end are if your speed is 0, the distance it’s trying to travel is 0, or the time*speed >= 1, which I can’t see anywhere being the case with the code you’ve given 