Representation:

although an appointment to a post may have been "ultra vires", that does not prevent the subsequent existence of a contractual employment relationship: a tribunal must look at all the circumstances of the relationship and the parties' conduct to determine whether or not it is, in fact, one of a contract of employment.

For relevant general notes see Definitions and interpretation/contract of employment and/or Definitions and interpretation/effective date of termination (''edt'')