Any profit that you make from your trade(s) stays safe in your Upstox Trading account.
Now, the next time you wish to trade, you can simply add to that balance with Smart Transfer. Smart, isn’t it?
To understand this better, here's an example:
You have marked ₹4,00,000 as trading funds and have made a profit of ₹50,000 from your trades on the same day. This ₹50,000 stays in your Trading account; so you can re-use it for trading, the next day. However, if you choose to use the fund, you will have to withdraw it, manually.