In case of derivatives, the settlement of funds happens on the next trading day i.e. T+1, hence your fund balance will not reflect the profits made by trading in F&O until they are settled by the exchange.
Further, if the T+1 day is a settlement holiday, the intraday F&O profits will be available on the next trading day.
For more information you can check out the following FAQ explaining the effects of new upfront margin requirements.