It will end after you have made the agreed number of payments as listed in your proposal -- usually 60 or 72 payments. How much will be the remaining number of payments multiplied by your monthly amount ( plus any extra income, windfalls, etc. you are due to pay).
I am not qualified to give advice and can only state my opinions, based on my IVA experiences.
How long is it over, do you have an equity release clause? How much are your payments and when did your IVA start.
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