hey Tim, it's common for the 9-15mo. dog to seem to forget what they learned... shoot, they are trying out their adolescence. Some people can just "crack down" and review the rules with their dogs, and some people (like me) do better with the structure of a refresher class, so I would say it's up to you, but either way it's better for all of you to curb your doodle. A 12-mo old puppy can be way more destructive than a 3mo. pup.
I have a couple of GREAT trainers in my area, I wish I could refer you to one here in CO!