All hunt and peck with this “Update”, no easy way. Go to your OneStore directory ie:
c:\users\your-acct\AppData\Local\Packages\MicrosoftFlightSimulator_8wek\LocalCache\Packages\Official\OneStore
Go down the list til you find the PA bird. Delete the directory. Now go to where you bought it and redownload your purchased PA…put it into the Official Directory and go back to MSFS.