1. The property was registered in the name of your grand mother who later made a will. When was the partition deed made then? What necessitated the partition deed when the will was already made?
2. You have not mentioned if your grand mother is alive or not.
3. If a will has been made by your grand mother of her properties then the will take effect after her lifetime. According to the will your aunts have no share in the property.
4. Your father and uncle alone have share in the property if your grand mother is dead. During their lifetime their children have no share therein.