Hi Gail, sorry to hear you're having some sleep troubles at the moment.
I think the 1st thing to work on is to get him to take 1 nap rather than 2. Its great that he is doing an earlier bedtime. He should wake up better rested and should be able to stretch in the morning. To get him napping once a day, you could either do a mini catnap in the morning (like 10mins at 9am) & then shoot for a longer nap in the afternoon (no later than 12.30pm) OR keep him awake until 11isham & let him have 1 long nap then. The mini catnap never worked for my DD since she was 16 months so if 10mins is enough to refresh him for the whole day, I would keep him up until 11/11.30. I know that a long stretch but try to take him out of the house, provide him lots of stimulation, out in the park, running around, playing with the ball, etc.... Then once you get closer to nap time, do a longer windown routine... something relaxing so that he goes down for a nice long nap. If he successfully takes a long nap, put him to bed at 6/6.30pm & keep doing the same thing until he is steadily taking that 1 nap. Then you can start pushing that nap to midday and bedtime at 7pm & hopefully a wake up of 6am.
I wouldn't do the milk or diaper change in the morning cause the milk is a prop and changing nappy will wake him right up. I would do wi/wo until the time you want him up
https://babywhispererforums.com/index.php?topic=63896.0. When he is up, is he happy to lay in bed until you get him or does he start calling out for you straight away? If he's happy leave him until you are ready to start the day. Delay milk until the desired breakfast time otherwise his stomach is trained to wake for food straight away.
You can try W2S in the morning (about an hour before he wakes up) but you need to stir him (so move blanket or stroke his arm or something) and then leave. W2s is usually for habitual wakings but I believe in your case his waking is from the schedule and incorrect nap times.....
How is he sleeping at night? Is it SOLID 11hrs or does he wake often and require your attention....
hth & let me know what you think
Layla