If you are currently renting and its not going to alter the ability to make your IVA payments I believe its fine, you would need to inform your IP though. If you own your own home and are subject to the equity release clause then its going to be a bit more complicated. The best advice is to approach your IP with your specific reasons and take it from there.
Anything is possible during an IVA, so long as creditors do not get prejudiced - or if they do that they agree to revised terms. Are you a property owner, with a fourth or final year equity release clause?