Companies pretend to make roles redundant. Some actually do out of necessity but really if they want to bin a salesman and hire a salesman they’ll do that in spite of employment law.
it's because they committed no sackable offence none of them will sign a contract saying if we don't meet these requirements we get sacked with no pay off as so much is out of their control
In all managers contracts I assume they'll generally be a severance fee should they choose to sack them rather than having to pay out the contract. It wouldn't make sense to have to pay the whole thing out with the lengths of the contract and the frequency managers get sacked.