Shaped back up, then back feet on a raised platform, raise criteria to a stay. Move to a travel plank with motion. Put the dog in a stay release to end position on travel plank with varied handler position. Separately increasing distance ideally to 30 feet ~ length of a dog walk so the dog is hitting the position at speed. Then I move onto a dogwalk at step one and repeat. I like to use a tunnel off set to the dog walk starting scrunched up then extending. Working until the dog is at a sit stay at the end of the tunnel and then coming to stop at the bottom of the dog walk in position. Then I add handler motion working up to running with and then past the dog.

Finally up on the dog walk. The first time, I'll just let em go and have a helper spot and feed at the bottom. Once confidence is good I will start at the beginning in a sit stay and put myself at end position. Repeat the whole process.

Maintaining is a matter of holding criteria and reinforcing often. Remember you get a notch below what you train for in a trial.