raely it can take one month mosttimes 3-4 months sometimes longer
Remember she is carring several eggs, one hook up does not mean all the eggs are fertilized so the longer the match up the moer eggs. hopefully.
When she decides she is done she will start forming shells around those eggs and then it is a couple months till she lays and then 2 more months until they hatch. Yes she can carry fertilized unshelled eggs in her for as long as she thinks she needs too. well within a reasonable amount of time.
Hence someone buying a first time snake and 6 months later, surprise.