A baby will stop waking for overnight feeds when they are no longer needing a feed or your reassurance.
Most babies will be able to take more milk around the same time the circadian rhythm hormones become influential.
So around about 5 months your baby will be able to sleep for longer blocks of sleep occasionally, but may well still need a feed once or twice overnight; this is normal.
As the circadian hormones become more influential at around 6-7 months your baby may wake just once overnight if at all.
Studies have shown that it is around this time that about 1/3 of babies are continuing to wake overnight and this is considered quite normal.
We often rush to get baby sleeping through, but sometimes in our haste, we interfere with their normal development of night sleep and we have a baby who is then more unsettled and resisting sleep.
A dream feed may be introduced around 6 months of age as well.