Best Practices for Introducing Levels in an Existing Advocacy Program Without Losing Past Contributions

Hi I am setting up levels for my existing advocacy program... I am eager to know when I introduce advocates to levels, there is a high chance some of the activities they have already done this year... Do you suggest we start from zero or acknowledge the activities done and plan the levels in such a way that they have new acts of advocacy to get involved in and complete that level with the remaining activities and move ahead?