(a) Representation petitions may be filed by:

(1) A labor organization which wishes to be designated as the exclusive representative for collective bargaining by the GAO employees in an appropriate unit, or by a labor organization which desires to replace another currently having that status;

(2) An employee or a group of employees (or an individual on their behalf) desiring a new election to determine whether a labor organization has ceased to represent a majority of employees in a unit;

(3) The GAO if it has a good faith reason to doubt that a majority of employees in the bargaining unit wish to be represented by the labor organization which is currently the exclusive representative of those employees;

(4) The GAO or a labor organization currently recognized as an exclusive representative desiring the Board to clarify an earlier unit determination or certification;

(5) Any person seeking clarification of, or an amendment to, a certification then in effect or any other matter relating to representation.

(b) Notwithstanding the provisions of paragraph (a) of this section, no petition may be filed which seeks representation rights for employees in a unit—

(1) Where an election has been held within the previous 12 calendar months and in such election a majority of the employees voting chose a labor organization for certification as the unit's exclusive representative, or

(2) Where an existing collective bargaining agreement having a term of three years or less is in effect, unless the petition for exclusive recognition is filed not more than 105 days and not less than 60 days before the expiration of the collective bargaining agreement, or

(3) Where an existing collective bargaining agreement having a term of more than three years is in effect, unless the petition for recognition is filed not more than 105 days and not less than 60 days before the third anniversary or any subsequent anniversary of the collective bargaining agreement.