You kind of get to know when they want feeding, their cry is different and they root around on you or start trying to suck whatever is near their mouth (clothes, shoulders, hands etc). I always nappy change, wind and cuddle first then feed if he's still crying, which he nearly always is!!
I've had to feed mine on demand as he literally screams until he loses his voice whenever he is awake unless I feed him, because he has colic, most times during the day he feeds really well gulping it down for 20 mins then he'll go 1.5-2.5 hrs before next feed, on an evening his colic is bad so he'll cluster feed and be on me for 3 or 4 hrs on and off with sometimes only minutes between, but he's not really drinking, he messes around much more and its more for comfort. However when he does go down for the night finally around 11pm he tends to sleep for between 3 & 5 hrs (depending on how awake he's been) then he wakes himself up and I nappy change and feed him and he will gulp it properly and we get another 3 hrs, he will cluster feed a bit in the morning as he's more hungry cos of not feeding much through the night.
its almost a routine but he's decided it, he has put on a lot of weight (from 6lb 11 to 8lb 11 in 4 weeks) but he is not fat and he needed that weight as he was too skinny, now he is a normal size the health visitor says his weight gain and feeding will stabilize. I guess every baby is different and bottle feeding is different to breast as u can see how much they are getting so could probably do a set routine, with mine I can't tell if he shouldn't be hungry as I don't know how much he has had because he's breast fed so I have to trust what he is telling me.
Also if breast feeding in the first week whenits colostrum they only get a few drops its like taking a pill with all your nutrients and calories your getting what you need but your tummy feels empty and u still feel hungry, so they do cluster feed way more, also this is their way of helping your milk come in and for it to be a good supply, so I'd say don't fight it and feed when they ask even if it feels completely over the top and they've fed 10 times in the last 2 hrs!!
Like I say this is only my experience, but I wouldn't overthink it or worry too much it will all fall into place when Lo is here!!