Child Care Costs Disregard for carers?

I have an odd feeling my client may be right about this, and all the online calculators seem to agree, I just can’t find the relevant reg to convince the local authority of the same…

Client’s partner works full time.  Client receives carers allowance for their eldest child, who is on mid rate DLAC, 2nd child gets lower rate DLAC, & the family pay child care costs for their youngest two children. Tax Credits have taken CCCs into account & awarded additions for this. However HBens have not, even though their own webcalc (ovaltech) suggests that they should.

Anyone got their regs head on? Or am I barking up the wrong tree - and uncovered an anomaly in the regs between HB & TCs

Unfortunately, DWP chose not to amend the HB regs (reg 28) to mirror that route to WTC child care element in HB childcare disregard.

Blast. Makes the TC disregard kind of pointless for most folk then.