Hi harlequin and welcome to the forum
Your partner's income is only taken into account insofar as your Supervisor will want to ensure that you are only paying a fair share of shared houshold expenditure and living costs in proportion to your combined salaries.
For instance if your new partner earns twice as much as you, then they should be paying twice as much of the rent/mortgage, gas, electricity etc and housekeeping costs than you are. This may alter the amount of disposable income you are able to continue to pay your creditors.
Regards, Melanie Giles, Insolvency Practitioner for over 20 years.
For further details contact me at
http://www.melaniegiles.com and view my IVA blog at:
http://melaniegiles.blogs.iva.co.uk