"Fixed Term Contracts (1) Part 10 does not apply to dismissal from employment under the contract for a fixed term of one year or more if – (a) the dismissal consists only of the expiry of that term without its being renewed and – b) before the term expires the employee has agreed in writing to exclude any claim in respect of rights under that part in relation to the contract …. (4) An agreement such as is mentioned in sub section may be contained (a) in the contract itself, or (b) in a separate agreement."
"….."renewal" includes extension, and any reference to renewal of contract or a fixed term shall be construed accordingly …."
"No dismissal in cases of renewal of contract or re-engagement (1) Where – (a) an employee's contract of employment is renewed, or he is re-engaged under a new contract of employment in pursuance of an offer (whether in writing or not) made before the end of his employment under the previous contract, and (b) the renewal or re-engagement takes effect either immediately on, or after an interval of not more than four weeks after, the end of that employment, the employee shall not be regarded for the purposes of this Part as dismissed by his employer by reason of the ending of his employment under the previous contract."