Are they formally interlocked ( do you have one I&E and make one monthly payment? ). If so there might be a clause ( not always included) that the failure of one will automatically fail the other. However, even if this clause is there the creditors could be asked to vary the agreement and remove this condition, or the arrangements could be separated beforehand.
My opinions are merely that .. opinions based on experience. Always seek professional advice.
IVA Completed 23rd July 2013 .... C.C. 10th January 2014