Anti reflux milk

Since starting my baby on anti reflux milk, he’s been going longer gap without feeds. Most he’s gone without feed is 5 hours and he’s 10 weeks old. Should I be worried? Also I make 6oz but he usually drinks 4-5oz. I’m jsut worried because before he’d have milk every 3 hours, now it’s gone to 5 hour gaps sometimes. Also his stool has changed and is having massive blow outs x