Hi hilary and welcome to the forum
Your supervisor will need to be informed of this change in circumstances, and the extent to which your boyfriend will be sharing the joint household expenditure. If you have been funding all of the costs on your own up until now, then his contributions is likely to result in your IVA payments been increased.
The Supervisor may also want to see evidence of his earnings, to ensure that you are both paying a fair share of the household running costs in proportion to your individual salaries.
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