(a) Civil Cases. In a civil case, a prematurely filed notice of appeal is effective and deemed filed on the day of, but after, the event that begins the period for perfecting the appeal.
(b) Criminal Cases. In a criminal case, a prematurely filed notice of appeal is effective and deemed filed on the same day, but after, sentence is imposed or suspended in open court, or the appealable order is signed by the trial court. But a notice of appeal is not effective if filed before the trial court makes a finding of guilt or receives a jury verdict.