(a) At any time prior to the thirtieth day next preceding a primary, any person who desires to change the enrollment of his political designation, or who, although registered, has not hitherto enrolled as a member of a party, may appear before a member of the board or the clerk and state in writing, over his signature, the political party in which he desires to be enrolled, and that he subscribes to the policies of said party, and the board member or clerk shall cause the enrollment of the elector's political designation to be made or altered accordingly in the general and district registers. In such cases the signature of the elector shall be verified by comparison with his signature on the general and district registers before the change of enrollment is made. When an elector has applied for a change in the enrollment of his political designation, as provided herein, the board member or clerk shall, upon request, stamp or mark the change so made on the card evidencing the elector's registration, issued to him pursuant to subsection (e) of section 100 of this title.
(b) At any time not later than the thirtieth day preceding any primary, any qualified elector of the election district may petition the board to cancel the party enrollment of any registered elector of such district who has previously enrolled as a member of a party for the purpose of voting at primary elections, setting forth, under oath, that he has probable cause to believe that such elector is no longer a member of the party with which he has been enrolled, and also setting forth that due notice of the time and place when said petition would be presented had been given to the person so registered, at least 48 hours prior to presentation of the same, by delivering a copy of the petition to him personally or by leaving it with an adult member of the family with which he resides. If, at the hearing of any such petition, the elector against whom the petition is filed appears and certifies in writing that he subscribes to the policies of the party with which he is enrolled at the time of said hearing, the petition shall be refused, otherwise the party enrollment of such elector shall forthwith be cancelled. This subdivision shall become effective after the general election in 1964.