It took me some time to figure it out but I'm happy with the result.What's tricky about this setup is the uneven number of points between source and target so I had to find a way to remap the points in one of them so I can transfer the transition timing attribute. I know it's a bit confusing but when you see the setup you will know what I mean. I dont need to say that this is houdini so you can tweak the hell out of this setup's parameters.
Download here.