The 11 hours of nightsleep is within the normal range. If you would like to start giving Ethan a later bedtime, that *may* help him sleep in later, but he will probably need up to a week to adjust and start sleeping later. I would recommend 7pm, as opposed to 8pm, since 7pm will be an easier adjustment for him. Is there anything happening at 5:15am that could be waking him up that he is more aware of now? (For example, dad getting ready for work, or something of that nature.)
He may also need a later naptime in order to take a longer nap. My son was taking short naps until I moved him to a 2-2:30pm naptime- he's up between 7-8am, and his naptime is consistently between 2-2:30pm. When he was younger, I had to avoid him being overtired to make sure to get longer naps. Now that he's a toddler, too short of an awake time seems to have a much larger affect on him. Maybe Ethan would benefit from a 12:15pm-ish naptime?
I don't know if any of this advice helped. I'll be watching for a follow up post

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