1)
SECTION I: ADMINISTRATIVE AND NON-TECHNICAL
A. AUTHORIZATIONS: The station license, construction permit, renewal certificate, auxiliary transmitter authorization, special temporary authorization (STA), and/or any other instrument of authorization shall be readily available and easily accessible at the station's principal control point. Renewal certificates should be associated with the corresponding station authorization. [See 73.1230(a), 73.1635, 73.1670, 73.3533, 73.3536, 73.3537 and 73.3539]
IOW, once you have the CP, file it and remove the application
2) see above : "and/or any other instrument of authorization" includes STL and RPU licenses
3)
(a) OWNERSHIP REPORTS: For station licensees who are not sole proprietorships, or partnerships comprised entirely of natural persons, does the public file contain copies of ownership reports and supplemental ownership reports filed with the Commission, including all exhibits, letters, and other documents associated with these filings? [See 73.3526(e)(5), 73.3527(e)(4) and 73.3615]
(b) RETENTION OF OWNERSHIP REPORTS: Are the ownership reports retained until a new, complete ownership report is filed with the FCC with a copy placed in the public inspection file? [See 73.3526(e)(5) or 73.3527(e)(4)]
in other words, once a new ownership report is filed and a copy placed in the PF, the old one can be removed