Oz per hour?

Feel like I’m constantly questioning whether I’m doing the right thing every time my 4 weekers routine changes! I formula feed and I’ve noticed my little girls ‘routine’ or feeding pattern tends to be she’ll take as many oz as hours she goes inbetween feeds, for example 4 oz every 4 hours, or if she stretches to 5 hours she’ll take 5 oz. Today we’ve decided we wanted to go 6 hours, she’s just polished off a 5oz bottle and I’ve had to give her her dummy after to soothe her (she’s a big comfort suckler!).. now I’m thinking, should I be offering her 6 oz? I know they’re all different and we feed on demand but it just feels too much to offer 6oz at once and also 6 hours inbetween feeding just feels so long! She’s got reflux too so we’re always battling that after feeds too, despite keeping her upright for 30 mins minimum after feeding.