(a) Except as otherwise provided in section 43-1241, a court of this state which has made a child custody determination consistent with section 43-1238 or 43-1240 has exclusive, continuing jurisdiction over the determination until:
(1) a court of this state determines that neither the child, nor the child and one parent, nor the child and a person acting as a parent have a significant connection with this state and that substantial evidence is no longer available in this state concerning the child's care, protection, training, and personal relationships; or
(2) a court of this state or a court of another state determines that the child, the child's parents, and any person acting as a parent do not presently reside in this state.
(b) A court of this state which has made a child custody determination and does not have exclusive, continuing jurisdiction under this section may modify that determination only if it has jurisdiction to make an initial determination under section 43-1238.