All eyes here: Futures and Options traders must take note of these changes! All eyes here: Futures and Options traders must take note of these changes! While these changes will be effective from October 28 (a day after October expiry), the contracts, for which they will be applicable, will vary. Here is a quick summary: Karan Dsij / Sunday, October 2, 2022 / Article rating: 4.5 As per NSE circular dated September 30, a total of 37 stocks will see changes in their F&O lot sizes due to the relevant price movements.