CRA indicates that an Appeals Officer can (and may) increase the reassessment under appeal

CRA stated that it has the authority under ETA s. 301(3) (equivalent, although not identical, to ITA s. 165(3)) to further increase a reassessment that has been objected to (for example, if a second valuation prepared for the Appeals Officer produced an even higher valuation) – but indicated that “[a]ny upward adjustment must be approved by the Appeals Officer’s manager or the Chief of Appeals.”

Neal Armstrong. Summary of 7 April 2022 CBA Roundtable, Q.1 under ETA s. 301(3).