If im not mistaken, Bandar Utama park & ride station is operated by a third party under Bandar Utama City Corporation (BUCC). I'm not sure about their terms and conditions (TNC). However, if you park your car within 24 hours on that particular day, flat rate of RM4.00nett or RM4.30nett (This you need to check) applies. But only if you are using the MRT, as you need to scan your card to enjoy the flat rate.