Options Expiry Date


I was looking for an option that expires on 14th April (Thursday) but can’t find any on Zerodha. However there are options which are expiring on 13th (Wednesday). What is the underlying logic behind this? I was under the impression that all options are supposed to expire on Thursday in India.

Thursday (14th April) is trading holiday, so the expiry will be a day earlier ie. on 13th April. Whenever there is trading holiday on expiry day, expiry will be a day earlier.