The claimant was a fetus in utero at the time of the accident and born prematurely four days after the accident. She was diagnosed with cerebral palsy as a result of her premature birth. The insurer initially paid accident benefits based on a medical opinion, but subsequently questioned causation based on an opinion of an obstetrician. While the claimant filed applications regarding entitlement to attendant care benefits and other accident benefits, the insurer filed the subject LAT for a determination on the causation issue. The claimant argued that the limitation period applied to the insurer changing its position on causation. All of the applications were consolidated into a single dispute and a preliminary motion was heard to decide whether the insurer could change its opinion on causation two years after the accident in reliance on the report of its obstetrician. Adjudicator Grant concluded that the insurer was not precluded from arguing causation at the subsequent hearing. There was no evidence of waiver because the insurer would have had to be shown to have full knowledge of the facts and choose not to assert its right to deny a benefit. Instead, the insurer acted appropriately by approving benefits while it sought to obtain an expert opinion on causation. The insurer’s approval of attendant care benefits did not waive its right to revisit causation and conduct future IEs. Further, the limitation period did not apply to an insurer’s defences. Section 56 only applied to denials of benefits. The claimant also argued that the obstetrician’s report should be excluded because it was obtained by the insurer’s legal counsel. Adjudicator Grant rejected the argument, reasoning that the insurer had provided the claimant with an IE notice and its counsel was simply acting as an agent.