"27. In our judgment, the Respondent [employer] did commit a fundamental breach of contract in seeking to impose unilaterally new terms and conditions in the form of a fixed term contract in a manner not permitted under the original contract. The Applicant did not unduly delay her response, giving notice by her letter of9 December 1993 in reply to the Respondent's letter of3 December 1993 . The notice expired on5 January 1994 , which was the effective date of termination. The Applicant was constructively dismissed.