There’s no built-in way to change which the starting anchor point is going to be, but you can get clever with the dash segment, gap, and offset values since these are animatable. In fact, the line draw setting just uses these under-the-hood.
First, note that if you hover over the line draw/dash popup menu, you get a tooltip that has the length of the path. This can be used for your calculations.
Let’s say you had 4 keyframes evenly spaced and wanted to start the animation at the 3rd one - this would represent 75%. If the Length value is 120.0, then this would be at the position of 90. So for this type of animation you’d use these values:
Then you’d make an animation that changes the values to:
(One small note is that it appears there is a bug with updating the first segment value - it will not immediately show on the editor. This has been fixed for the next version of Hype. A workaround is to modify the dash gap or offset value and those will update the entire path)