What is the procedure under GA state child custody laws to seek custody modification

I am admitted in Georgia.

Run to your local family court and file a petition for a modification of custody. Have her execute a stipulation giving you custody and file it with the court which will enter an order on consent.

Do not leave the matter alone. Federal law compels the use of the court in everything involving children. Suppose you had custody but owed the mother child support. The court cannot waive arrears retroactively. This means if you have a child support payment going to her, she can claim it even though you have the child unless you go to court to shut it off.

So file now.

You will need to file a modification of child custody petition. Georgia Superior Court judges now require a parenting plan that will set out visitation, child support, ect. You can file this in Fulton County since all of you live in Fulton County. And you can agree to the terms of the parenting plan and have the Court enter an order setting it out as the new custody order for you, your ex and your children. The process should be relatively easy since you all agree.