Any PPI reclaims go to the IVA even after it has completed. Never use a PPI company without the permission of your IP as you could find yourself with serious bills to pay.
I think it's a bit cheeky to expect creditors to write off debt then claim back PPI. However, it's your right if you feel it was mis-sold.
Now that it is a hot potato, creditors seem to be not paying direct to debtors if they were in an IVA previously. It will go to the IVA company to be distributed to creditors.