SDP erosion

Hello, can I just check my understanding?
Cl has just claimed UC after a relationship breakdown. She was partner of a claimant on income-related ESA previously and the award included an SDP in respect of her as they both were in receipt of PIP DL and no one was claiming CA for looking after her. She was not the ESA claimant so has now started the WCA process on UC. She is still in receipt of CA for her ex-partner so the first AP will include SA, child elements, carer element, housing costs element and transitional SDP at £285pcm.

If found to have LCWRA, as seems likely, she will lose carer element as it will be replaced by the LCWRA element, and her transitional SDP will erode completely, leaving her worse off overall by £80.80pcm (285 + 185.86 - 390.06). 
Thanks