We have a pending PCT application. What is the deadline for entering the national phase in India?

Thirty-one months from the earliest priority date. This is prescribed by Rule 20(4)(i) of the Patents Rules, 2003, and applies whether or not a demand for international preliminary examination was filed — India does not operate a 30-month/31-month split.

If the requirements of Rule 20 are not met within that period, the international application designating India is deemed to be withdrawn under Rule 22. There is no separate "late entry" route in the Act.