I'm not 100% sure, but I know with the Wonder Weeks book/app, it says the developmental milestones go from the bubs EDD, not when they were actually born. That's for term babies, I'm not sure if it would apply to prem bubs though, but to me it makes sense that it would. Have you got the app? Maybe give it a try (you enter bubs EDD and it shows you when each leap is coming up, tells you what's happening etc.)
Is it available on Android? I'll have a squiz. Thanks PZ. I'll have a go!

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