Thank you. Whilst they do have the right to change your terms in relation to the products you sell, etc, they still need to ensure that this is done fairly and reasonably. There is still the requirement to preserve the mutual trust between employer and employee, which is something which exists in every employment relationship.
Therefore, if they do something which compromises that implied requirement and basically they act in breach of that trust, it can give you the right to challenge them. However, this is not easily done, generally these claims can only be made by resigning and making a claim for constructive dismissal.
The potential solution, which I mentioned, is that they at least consider providing some payments to 'bridge' that transitional period, which would reduce the effects this change has for you. However, if they flatly refuse to do this and just steamroll the changes through, all you can do is consider raising a grievance to challenge them internally and if that does not work, all you can do is consider resigning and pursuing the constructive dismissal claim.
It is worth mentioning that there is a possible alternative solution, where the employer is approached on a 'without prejudice' basis (i.e. off the record) to try and discuss the possibility of leaving under a settlement agreement. Under such an agreement, the employee gets compensated for leaving the company with no fuss and in return promises not to make any claims against the employer in the future. It is essentially a clean break, where both parties move on without the need for going to tribunal. However, it is an entirely voluntary process and the employer does not have to participate in such negotiations or agree to anything. It just means that these discussions cannot be brought up in any subsequent tribunal claim and prejudice either party. So there is nothing to lose by raising this possibility with them as the worst outcome is they say no, whereas if successful it can mean being allowed to leave in accordance with any pre-agreed terms, such as with compensation and an agreed reference.
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