The amount of the basic award shall be two weeks' pay where the tribunal finds that the reason (or, where there is more than one, the principal reason) for the dismissal of the employee is that he was redundant and the employee—
by virtue of section 138 is not regarded as dismissed for the purposes of Part XI, or
by virtue of section 141 is not, or (if he were otherwise entitled) would not be, entitled to a redundancy payment.