Hi, Orders last until discharged or new orders made. Or until child is 18. If someone moves away making the current orders impractical or far from an ordered area etc a recovery order can be issued enforcing the return of the children to the agreed area or region. Sometimes if other parents refuses to return the children are then ordered by the court to reside with other parent. Courts will sometimes give an ultimatum to the parent who has removed the child. For information specific to your situation definitely see a Lawyer. If you are on the Gold Coast or Brisbane I can definitely recommend a few different people for you :)

Happy to answer more questions if you have and I can also post some links to further info if you want