Yes, it is valid within the trading day. Generally speaking, trading funds on weekends is not recommended. The fund trades at T+ 1 If you buy a fund on a trading day, it is calculated according to the net value at the close of the trading day. The share is confirmed on the second trading day, and the income is calculated after the share is confirmed.
Fund trading hours: Monday to Friday, 9: 30am-1:30am, afternoon13: 00pm-15: 00pm, and trading is not allowed on legal holidays.