(a) Certifications. The FLRA issues an appropriate certification when:

(1) After an election, runoff, or rerun:

(i) No party files an objection or challenged ballots are not determinative; or

(ii) The FLRA decides and resolves objections and determinative challenged ballots; or

(2) The FLRA issues a Decision and Order requiring a certification.

(b) Revocations. Without prejudice to any rights and obligations that may exist under the Statute, the FLRA revokes a recognition or certification, as appropriate, and provides a written statement of reasons when:

(1) An incumbent exclusive representative files, during a representation proceeding, a disclaimer of any representational interest in the unit; or

(2) A petition is filed and, due to a substantial change in the character and scope of the unit, the unit is no longer appropriate and an election is not warranted.