Am I reading it right - but your day has 2 sleeps written out not 3? Or is there a sleep between 3pm milk and dinner? Because that would look pretty similar to my DD's days but sometimes that last sleep just doesn't happen. I had wondered whether to try and get her into a more consistent 2 nap day but have decided to not bother actively managing it. If her first 2 naps are of a decent length then I don't try to put her down for the 3rd one. If they've been quite short then I try and put her down for the 3rd one but I don't stress if she really fights it (and usually will get her tea on a bit quicker to make sure bedtime is earlier rather than later).
DS used to have a similar routine to yours, as he was a very early riser (still is, sigh) so needed the extra nap. Used to wake 530/6am, slept from 8-9am (in cot) another nap around 12 (usually in buggy) then a later afternoon short nap (always in buggy and this was a battle but he ended it to go through to evening). He was about 15 months when he dropped down to 2 naps. I started stretching the morning nap to 10 and he slept for longer, and then he had a afternoon nap about 3ish but I found he always woke (or was woken) from this one grumpy. Eventually, when he was about 18 months, his morning nap started around 11am and he had a good couple of hours, meaning I could cut the afternoon one. Even now, his optimum nap time is around 1130, though at nursery he naps at 1230.
DS will nap in the car but I prefer to be home because he gets his full nap time then (and I can have a nap too!).
At this age (and up to about 16 months), I did the 2/3/4 routine - so, up for 2 hours then short (about 40 mins to an hour max) nap, then up for 3 hours and then long (up to 2 hrs) nap, then up for 4 hours, then bed.
So a typical day: 7am - 5/6 ozs milk 8.30 - breakfast - porridge, toast, a little more milk, maybe banana too 9am - short nap in cot 12.30 - lunch 1-3pm - long nap in cot 3pm - 5/6ozs milk 5pm -evening meal 6.30 - bath then 6oz milk 7pm bed