My twins are nearly ten weeks old, but were nine weeks prem. They are on a four hourly feeding schedule and stick to it well so we only wake once in the night at 2am. I know we are pretty lucky for such small babies to be in that routine (this was established in SCBU before they came home).
I'm wondering how you count their age though in terms of starting to get them to push through the night - is it from their birth age or their corrected age. I certainly don't want to push them when they are still so small! I think at the moment that one would miss the 2am and go through to about 4, but as her sister wakes up I am waking and feeding her (she takes the whole bottle). I dont really want to end up with them on a different feeding schedule for my own sanity!
I can't answer your question really but I would leave well alone.....one waking each night sounds like heaven to me! And they will sleep through when they are ready. That's what im told anyway!! Good luck whatever you decide to do.