hi and welcome

if his day is 630am to 630pm, then i'd definitely be trying to keep him up after that 7am feed. this is the one to work on so that the rest of your day can be on more of an EAS routine than ESA. if he is up at 630am then you could feed him a little earlier too, i wouldnt do it straight away as you dont want him to get used to eating as soon as he wakes, but maybe 645?? and then follow with some play time. once he starts showing tired signs, switch to some low key activites (walk around the house or garden, look out the window, sing some songs, read stories, cuddle with some soft toys, etc).
rather than jumping to a 4hr routine just yet, lets see if we can get him back onto a 3hrly routine in the right EASY order first. so if he is waking at 630am, aim to keep him up til as close to 745 as possible and then do wind down aiming to have him in bed and sleeping at 8am (watch his cues, if he's falling apart then put him down earlier and you'll have to extend more gradually over time). let him sleep as long as he wants up to 2hrs.
i'd keep feeds to around 3hrly for now and work on extending it once he gets used to some A time after E again. if he wakes early then it's fine to do AEAS but definitely work on having at least some A time after E even if it's just 15 mins.
let us know how you go. also future posts could you please write your routine as follows as it's just a bit easier for us to see what is going on:
E (when, how much?)
A how long (remember this is from eyes open to next sleep)
S when and how long? also note if he takes a while to settle to sleep or if you need to resettle during the nap.