hi - as far as 7am starts - they are really luck of the draw in my opinion. every baby is different and although you don't want your baby up at 5am thinking it is a good time to start the day, it is just normal for many babies to wake sometime between 6 and 7am to start their day and i woudl personally not stress too much about starting at 6:30 vs 7am if you can get the rest of your day running smoothly and get lo to sleep through eventually (there are a lot of people whose baby wakes at 7 but it is after a night feed at 3am, i'd rather have no feed :wink: )
you have your lo awake for 1hr 45 for each cycle and then he naps for 1hr 15. are you waking him up from his nap in order to stick to a 3 hr feed?? if you are, then i would say to let him sleep a bit longer at these naps (as long as he is happy sleeping up to 2hrs i woudl say). if he is waking at 1hr 15 each time - how is he when you put him down at 1hr 45?? this is quite a long awake time for 13 weeks. if he goes down for his naps without a problem (nothing more than a little settling fuss) then ok - but if he is needing your help to settle and is fussing a lot for a while, then i would say he needs to go down a little earlier. try 1hr 30 and see if his nap lengthens a little?
are you breast or bottle feeding? how much/well does he feed at the 6, 8 and DF feeds?
if he is not taking a lot at 8 and DF i would try to get rid of the 8pm cluster and that way he will be hungrier at the DF and take more then which can extend his night sleep a bit.
a 3am feed at 13 weeks is totally normal! he will naturally eliminate this soon enough. in the meantime what you can do is try to get as many calories in him as you can between 7 am and DF. you can also try moving the DF to 11pm and see if that helps (especially if he has not been taking too much, this way he is hungrier and takes a bigger feed)
let me knowabout these things and we can see if anything helps. sorry with limited info i asked questions and made comments based on possibilities - if i am off base at all let me know and i can try again to give more specific advice.