South Africa became a republic under the Constitution of 1961 and the Monarch and Governor-General were replaced by a ceremonial State President.
The Governor-General was appointed for an indefinite term, serving at the pleasure of the monarch.
After the passage of the Statute of Westminster 1931 and the Status of the Union Act, 1934, the Governor-General was appointed solely on the advice of the Cabinet of South Africa without the involvement of the British government.
In the event of a vacancy the Chief Justice served as Officer Administering the Government.
In the event of a vacancy the Cabinet would nominate a member to serve as Acting State President.