I will be ending my current service with another refuse provider before the 7/1/20 start with Republic. Can I setup an individual account with Republic Services for a few months before the new contract?

This is not recommended.  It will highly contaminate the data entry conversion and container inventory selected in the surveys.  Please schedule the removals of your containers with your current provider (other than Republic) for a date close to 6/30/20.  This will prevent you from being without trash/recycle service for an extended period of time.