This summary is not the rule. The rule text controls.
If you're serving as a fiduciary (like an executor, administrator, guardian, or trustee) and you want to step down from that role, you can ask the court for permission to resign. You do this by filing a petition at any time, explaining why you want to leave the position. Your petition needs to lay out the specific facts and reasons behind your request.
Along with asking to resign, you also ask the court to cancel your official appointment (your "letters") and to let you settle your final accounting. This accounting can be done formally through the court or informally, depending on what the court allows. The court will decide who needs to be notified about your resignation request and how that notice should be given, which usually means other interested parties in the case, like beneficiaries or co-fiduciaries, will get a chance to weigh in before the court makes a decision.
This rule matters because a fiduciary can't just walk away from their duties without court approval. It protects the estate, trust, or person you're responsible for by making sure someone reviews your reasons for leaving and confirms your final accounting is in order before you're officially released from the job.