The claimant was involved in an automobile accident in October 2020. She applied to the LAT seeking CAT determination under Criterion 8 and entitlement to IRBs. The LAT denied the claimant’s request to rely on a late-filed supplementary hearing brief as the prejudice to the respondent outweighed the probative value of the documents. The LAT found that the claimant was CAT under Criterion 8 due to marked impairments in three spheres of function, including Adaptation. Despite the CAT determination, the LAT found that the claimant was not entitled to post-104 IRBs. The LAT confirmed that applicants bear the burden of proving they meet the test and criteria for benefits, and the claimant failed to demonstrate entitlement to post-104 IRBs, in part due to her failure to tender expert opinion evidence addressing post-104 IRBs. In contrast, the insurer tendered expert opinion evidence on post-104 IRBs, which the LAT relied on for its decision.