Hey there.
Congrats on the upcoming litter!
Well the average piggy is pregnant for about 114 give or take a few. Do you have a rough idea when she took? If so I would take the earliest date possible & go with that, and move her a few days prior to that date.
Some signs to look for in a pig going into labor -
These signs usually happen in the 24hr prior to the birth
•pawing with it's teeth, like it's making a nest
•check her udders, they will become firmer & fuller/bigger
•will begin breathing heavier, from a normal 25-30 up to about 80
•a bloody discharge & potential fecal matter will be expelled
•may become very quite while looking for a spot to lay down to have the piglets
If you come across her laying on her side with her legs shivering, then there will be little piglets very shortly & should do whatever you can to create as clean a setting as possible for their arrival.
I hope that has helped some, my friends have pot bellied pigs that they breed.