The AA Option, when configured for speed based on Part Length, the following change has been made.

When transitioning from a longer part to a shorter part, the speed reduction will take place one part early. This will provide time for the speed reduction to take place before the shorter part is run.

When transitioning to a longer part from a shorter part, the speed increase will occur as it always has, it will transition to the faster speed, once the longer part becomes the actively running part.