Annual review confusion- am I being stupid?

kimplus8

Background is.
Ex hb has historically earned between £500-550 per week in income and has paid child support based on this amount via a DEO.
As far as I know the annual review is calculated at the recorded weekly earning for the previous financial year. 
At my annual review for 2024 his payments were recalculated based his previous years earnings which were £800ish per week which is a significant increase and is over 25%. 

A new monthly amount was calculated and was quite a bit higher than last year. 

He then proceeded to file a mandatory reconsideration claiming that he no longer earns this amount.

The CMS have agreed that from his last wage he is earning approx £500 per week again and have reduced the calculation accordingly as his income has reduced by more than 25%.
I am not questing the recalculation as they can only calculate based on what HMRC reports, but it is my understanding that he should have reported this increase in earnings and had a new calculation at the time he began earning more. 
He has effectively earned over £15000 more than what they have calculated and has not had his DOE increased. 

Am I not understanding the process or should they be backdating the increase in earning for last years Annual Review as that year he earned over 25% more.
If not does that mean a non resident parent can earn over 25% and at each annual review reduce hours etc to lower the calculation and then once it is completed start earning more again? 

Surely there should be some consequence for him not reporting such a significant increase in earnings? 

My kids deserve that money, he does nothing else for them which I know is largely irrelevant to the CMS but it is unfair they miss out. 

kimplus8

Can anyone help? 

MrsR1234

If he is as previously assessed on historic end of year income from HMRC then he had no legal obligation to advise them of an increase to his income. There will be no consequence as he was not required to report. As he is now assessed on income that he is earning now, rather than historical income, he does have a legal duty to inform of his income increases by 25%. This means that if his income increases by 25% going for ars, then it will be backdated to when that increase occurred. For you, right now, there is nothing you can do to change the amount, your only option is to appeal to HMCTs with your Mandatory reconsideration notice.