I guess my question is can P.A’s see new patients in Urgent Care?

I am auditing our P.A.’s who see patients Monday-Sunday in Ortho Urgent Care. My question is, if a new patient comes in to be seen and a P.A. see’s them for the first time. Would the P.A. be able to bill under their own NPI or because the patient is new and a treatment plan has not been established, P.A. would need to bill incident to and bill using the Supervising doc’s NPI? I think a P.A has to use their own NPI when supervising doctor has no involvement in patients treatment?

Any help is appreciated and if anyone has reference materials to back it up, that would be awesome. Thanks!