Yes. However, both parties must agree to the changes and file a stipulation to change parenting time, decision-making, or both. The courts could choose to deny the stipulation. If either party disagrees with the modification, the requesting party must file a motion with the court.
Even if both parties agree to the changes, the court can only enforce changes filed and approved of by the courts. It’s best to file a stipulation to protect the interests of all parties, including the children.