Sorry for the delayed response....we have been away for Easter so his routine has been a bit out of whack but in general, his day is something like this give or take 1/2 an hour:
700: Wake & BF
800: Solids
900: BF
930: Sleep
1100: Wake & BF
1200: Solids
1400: BF
1430: Sleep
1600: Wake & sometimes a BF
1700: Solids
1800: BF
1900: Sleep
Since he hit 4 months (where he was previously sleeping 7pm - 6am/7am) he has been waking overnight - usually in the early part of the evening (about 40mins - 1hr after he is put down) and sometimes requires a pat to get back to sleep, other times we have to pick him up. The past 3 weeks he has had 5 teeth come through and has had multiple other night wakings, but this is another issue for us to try and crack as I am not sure it is only teeth to blame.
In general, he usually is up for 2.5-3hrs in the morning before his 1st nap and then 3 - 3.5hrs in the afternoon for his 2nd nap. I haven't found activity time (either longer or shorter) to make much of a difference to whether or not he wakes after 30-45mins. As mentioned in my first post, it is not something that happens all the time but there might be a 2-3 days here and there where it occurs.