I had a loan with HFC Bank which was included in my IVA and 3 previous loans that were paid off in full.
When i came to claiming PPI, HFC tried to off set the refunds from my previous paid in full loans, against the loan which had been included in my IVA.
The ombudsman declared that they were not allowed to do that and that the refund from the paid off loans was to be distributed amongst all my creditors.
They are not supposed to -- but many creditors still attempt to and I know there are several ongoing cases where IP's are still arguing with creditors. HSBC is one such culprit.
My opinions are merely that .. opinions based on experience. Always seek professional advice.
IVA Completed 23rd July 2013 .... C.C. 10th January 2014
Again this is an area for the solicitors and the terms and conditions. Some proposals were modified by creditors when PPI first raised its head saying that any PPI would be set off. There is also a section in the R3 standard terms which deals with this but not sure about Protocol.