Remarrying - how can I avoid Notional Income variation on new partner's assets?

Hi all,

Thanks for reading.

I've been paying child maintenance for years now based off my income, as is the case for most people I guess.  Over the years my ex has submitted a few applications for variation for the reason of notional income, these have all been rejected by the CMS as all my assets generate income which I could prove I have declared. So far so good.

However I am remarrying later this year and am worried that my ex will submit more notional income applications relating to my new partner's assets - even if my new partner's house and bank account are in her name, as her husband I will have some legal claim over them.  I can't see anything in guidance or legislation that would prevent the CMS taking these assets into account.  For example, my new wife has ISAs worth more than the £32k notional income threshold, could it be argued that as her husband our assets are shared so I now need to declare 8% of their value as notional income?

I have asked the CMS the question and they have not been able to give me a clear answer, nor will they put any in writing so I can protect myself if their advice turns out to be wrong.

Anyone got any bright ideas as to how I get a definitive answer on this? My scenario may seem far fetched but given my ex has already tried a number of speculative notional income variations so there's a good chance she'll try again as she knows I am remarrying.

Thanks in advance!

J