Depending on your trading style, you might want to keep the position open for more than one day. That's totally understandable!
That's why it's allowed to hold trades overnight on all FXCI challenges.
Please note that holding trades overnight may be subject to swap fees. These small fees, also called rollover or overnight financing charges, are applied to maintain open positions. They're based on the interest rate gap between the traded currencies, essentially acting as rent for borrowing one currency to buy another.