Concept:
The Constitution of India provides a clear mechanism for continuity of the executive when the office of the President becomes vacant. The Vice-President temporarily discharges presidential functions until a new President is elected.
Step 1: Under Article 65, the Vice-President acts as President when a vacancy arises due to death, resignation, or removal of the President.
Step 2: Article 62(2) mandates that a new presidential election must be held within six months of the occurrence of vacancy.
Step 3: Since the election must be completed within six months, the Vice-President can act as President for a maximum of 6 months.