My ds2 is ten months old. A big boy too as he's on the 99th percentile!
He has been getting up at 4.30-5am since 4 months old.
He's just started crawling and his whole sleep pattern has changed. Up at 5.30-6am, sleeps about 11am for two hours in the buggy. Then it's bed around 7pm. Awake at 11ish for 7oz, and just this week he has dropped his 3.30am feed- but only because I have introduced a dummy.
It's attached to his blankies so now the dummy and blankie soothes him.
Maybe worth a try? Their routines will change on their own.
As for the cc, it's not for me personally. With ds1 he settled quicker and was more content through the day if he knew when he cried I'd be there. For me if ds2 isn't settling I offer milk, about a minute of slow pats on the back to check for wind while he's sat on my knee, then in his bed, dummy and blankie, sshh night night, kiss, walk out.
I do the same thing every night when it's bedtime. I never have to go in more than 4 times and regularly don't have to go back in at all.but I may just be lucky?
And always minimal talking, dark room etc.
Do you think he'll sleep in the buggy? I leave him in the back garden as its secure and I stay where I can see and hear him. But I manage to get cleaning etc done while he's asleep. Ds1 loved sleeping outside in buggy too- but obviously only if it's safe for you to do.