I must admit, it is very confusing being told one thing by the well respected experts on this forum, and then being told something totally different when I speak to DFD.
I've scoured through my copy of 'Standard Conditions for IVAs' that I received with the original proposal and I can't see any mention of what happens in the event of a creditor not submitting a claim by a certain timeframe.
I haven't ever had any direct contact with my IP, maybe I should have I don't know... like I've said before, I'm no expert, just trying to get to the end of my IVA, however long that ends up to be

If it is the usual practice to exclude non-claimants before the end of the term of the IVA, I too am intrigued as to why DFD don't do this.
If it is relevant, I was told by one of the people from DFD that I will pay the estimated amounts, and if they cannot get the monies to the creditors who haven't submitted their claims, I would get it back again, although no time-frame was mentioned for this and they said that rarely happens as most creditors want their money (of course).
To be honest, it all sounds needlessly complicated.