Please keep in mind that according to most peds, the definition of a baby "sleeping through the night" is one 6-hour stretch. I would considering closing the door at 8 and not opening it until 6:30, expecting a baby to sleep 10.5 hours!, to be unreasonable. He is doing one 5 hour stretch (8-1), which is really close to the 6 hours that is expected. It's just the timing that you should work on, because you haven't lined up his long stretch of sleep with yours.
If you want to get 1 longer stretch that starts and ends later, can you try doing a dream feed right before you go to bed? I did this with one of mine. I put him to bed about 9. Then I fed him again at 11 before I went to sleep - called a dream feed, because he basically ate in his sleep. It filled his belly, so that he could get his 6 hour stretch of sleep from 11PM to 5AM, which corresponded better to my sleeping schedule.
So, in your case, if your baby goes to sleep at 8, and you feed him in his sleep at 10 just before you go to bed, then you might get him to skip the 1AM feeding. You'll be more able to get up with him at 4, since you've had a longer stretch of sleep leading up to that.
OR - try to gradually push back his 8PM bedtime, 15 min at a time, until 9 or 9:30 and see if over time, that adjusts his sleep timing so he's getting up later.
ETA: I'm trying to say exactly what Margie also said...