Students need to start a Band new project for the Create PT. They cannot use or submit practice PTs for their Create PT. They can use snipets of existing code as long as they provide acknowledgment, reference or citation for the code.
From the AP Computer Science Principles HandBook
Section: Guidelines for Completing the Through-Course Assessment
You may not:
Submit work that has been revised, amended, or corrected by another individual, with the exception off cited program code;
Submit work from a practice performance task as your official submission to the College Board to be scored by the AP program; or
Seek assistance or feedback answers to prompts