The appellants appealed a trial decision granting the respondent an enhanced supplementary pension based on an additional 36 months of service.
The trial judge found that the parties had a prior oral agreement regarding the pension credit and were mutually mistaken in believing the written letter agreement reflected this intention.
The Court of Appeal upheld the trial judge's decision to rectify the agreement, finding that the appellants' attempt to take advantage of the mistake amounted to unfair dealing.
The Court also agreed that promissory estoppel prevented the appellants from denying the pension entitlement.