I'm really not an expert on these things, as we are having issues with our 2.5 year old (possibly getting better, though), but the thing that really jumps out at me from your routine is that there is 6 hours between wake up and nap, and 4.5 from nap to bed. I would be inclined to move the morning nap earlier so that the day is more equal - say 12.30-2, giving 5.5 am and 5.5 pm.
Having spent ages tweaking our routine (from 7.15 wake up, 12.30-2.30/45 nap, 6.45 bed) to find the magic formula, we have ended up with: 6.45 wake, 12.30-2.15 nap, 7.15 bed (asleep by 7.45) - this has worked for most of the week, so I am hoping that this might be a routine that we can go with for a while.
Not sure if any of this helps?
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