This case is a useful reminder that not everything in an employment contract is within the gift of the employer and employee - some things derive from statute and cannot be changed, regardless of any agreement by the parties. One of those things is the effective date of termination. The EDT is the date at which the clock starts running on claims for the right to not be unfairly dismissed.

Most statutory claims in the UK have a three month time limit, starting from the EDT, in which a claimant can submit a tribunal application to enforce his/her rights. The EDT is a statutory concept, set out in S.97 of the Employment Rights Act in GB and A.129 of The Employment Rights (Northern Ireland) Order 1996 in NI.

There are various options set out in statute, depending on whether the contract expires under a specific clause in the contract or whether notice is given or not given by either the employer or the employee.

Of particular relevance to this case are the words:

"...in relation to an employee whose contract of employment is terminated without notice, means the date on which the termination takes effect..."

Ms Parkin was employed as Managing Director and she was blocked from returning from a sabbatical to her MD position, although there was a "clumsy attempt" to consider possible alternative, lesser roles. This was found to be a dismissal without notice by the tribunal, notwithstanding that correspondence on attempts to reach a settlement were made and the claimant was put on garden leave three days after the meeting. The employer later issued a dismissal letter to include notice and a termination date 6 weeks or so after the original meeting on 1st September 2015. The claimant submitted a claim for unfair dismissal which would have been in time if the later date were the EDT but out of time had 1st September been the EDT.

The EAT ruled that the employment tribunal had found there was a dismissal on 1st September. The parties had lost all trust and confidence in one another from that date. Regardless of any subsequent actions by the employer to issue a termination letter with notice and agreement between the parties on what the actual termination date ought to be there had been a finding of fact by the tribunal that the contract had terminated without notice on 1st September. That date could not be changed (unless, presumably, the employee had been reinstated through an appeal and the 1st September date rescinded) by any agreement by the parties - it is set by statute - and the claimant's tribunal claim was out of time.
http://www.bailii.org/uk/cases/UKEAT/2017/0049_17_2706.html