Lucy - yay for Charlie finally taking the bottle AND sleeping through! That's fantastic! Now you will be well rested and stress free for your wedding Well... maybe just a bit more than before.
It's interesting what you say about sleeping through. When Gabby was given formula top-ups at hospital and again once I was home for a few days, it was so that she would sleep! I too believed that the formula bottle at night helped her to sleep through. It helped me to establish a night time routine and the bottle was a cue for Gabby to say "Ok, it's night time now. Go to sleep".
I have a few friends that have said they will try the same thing when they have their second babies. While I tell them it took a while before Gabby was actually sleeping through and it may not work the same for them, they still feel it would be worth giving it a go as their first children didn't sleep through until well after 6 months. One of them still wakes during the night for a feed and she is 1.5!
Another friend who has a little boy and girl twins said that she went to a conference where an expert doctor (can't remember his name) said that he believes a formula bottle at night is a great way of establishing a night time routine and helping bubs and mums to get some much-needed sleep. It certainly save my sanity!