They are not making it up as they go along, but merely complying with the terms of your IVA proposal which they are duty bound to supervise on behalf of you and the creditors. I personally feel that they ought to have taken all of the bank charge refund from you as well under the windfall provisions.
If you incurred any costs as a result of bringing the claim, then these should be allowable - such as unpaid time off work to attend Court.
Sorry - I know this is not what you will want to hear, but windfall provisions are a normal part of IVA contracts and you would have to hand over the money to a Trustee in bankruptcy as well.
Regards, Melanie Giles, Insolvency Practitioner for over 20 years.
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