Hi,
I take it he is breast fed, so it's not unusual to still be feeding a couple of times at night, but it sounds like he's started snacking a bit, particularly considering that he used to sleep through, and that could be causing the night waking.Can you stretch your ds to 4 hours, or even 3.5, during the day if you have some A time between sleeping and eating? Also, can you stretch his A times a little? My ds is almost 6 months, and usually goes around 2.5 hours between sleeps.
It does seem like he has a lot of day sleep, my ds does well on 2.5-3 hours during the day. Your ds is getting about 14 hours in every 24 (if my maths is correct!), but because he's getting about 4 hours during the day, that could be causing the early wakings - he is just fully rested at 5.30am.
I think if you stretch his A times out, and also stretch his daytime feeds out, he should take more each feed and so go longer stretches at night again.
Finally, does he fall asleep independently?