In general, there is a margin applicable for all the trades irrespective of a buy or sell trade, as per the peak margin requirement. However, this margin for a sell trade is not charged at the time of order placement since the exchange has issued guidelines to consider EPI (Early payin of shares) value.

Hence, if the same scrip is bought back by bringing in fresh funds at any given time during the day, it will result in short allocation of Margins and since there are no net delivery obligations, there cannot be any EPI value consideration. In short, this will amount to Intraday trade activity.

Based on the above condition, you only get 80% of the value of the sales proceeds to buy the same stock on the same Day in Cash once Sold provided you have not placed any order in Intraday, Cover, E-Margin, F&O and currency segments. If you have placed even a pending order in any of the above products viz. Intraday, Cover, E-Margin, F&O and Currency, you will not be able to buy back the stocks of the same security earlier sold in CnC on the same day. Similarly, buyback of shares in E-Margin i.e. roll over of E-Margin positions, earlier squared off from E-Margin open positions, will now be allowed to an extent of 80%.