Within 60 days of a statewide majority of backstretch workers having chosen to be represented by an exclusive collective bargaining agent pursuant to Article 2.5 (commencing with Section 19455) or any other law, and so long as a majority continues to be represented by the agent, that agent shall designate two representatives to replace two of the members if the CHBPA Pension Administrative Committee and the plan document shall be amended to provide for this representation.