Hi Nicky,
Have you already started the route towards your IVA or are you just thinking about it?
If it's the former then I can't see the IP being happy at you if you change to a repayment as there will be less DI for the creditors.
If the latter, then I would look at the figures if you change to see if an IVA is still an option before you change.
If the payments go up then you would have to go back to your IP to see about lowering your payments.
If you've not approached anyone then I suggest visiting
www.iva.com for a list of companies and reviews. Give one or two a ring for free and impartial advice.
Sharing from experiences of dealing with debt
The greatness of a man is not in how much wealth he acquires, but in his integrity and his ability to affect those around him positively.
Bob Marley.
http://kallis3.blogs.iva.co.uk