sleeping through the night - when is too early?

So I have been blessed that my two month old twins have slept through the night the past three nights (when I say sleep through the night I mean from 12-5) is this too long between feedings and should I be waking them ? During the day they eat every 3 hours and don't need to be woken up for this they do this on their own - any insight on this would be greatly appreciated.