Watch out for a regression, it does happen sometimes. Just do what you have been doing. It happened after 7 nights with Alex, just when I thought I'd cracked it, I cracked a bottle of wine. I don't advise the wine until Grandma comes to babysit!!!
Glad things are going well. Good work, you might be able to adjust the 6am, but I would work on the sleeping through first and see if you can change a routine when he is more settled.