Switching to IRESA from CBESA in a UC live service area

My 61 year old client is on Contribution based ESA- support group. She is single and had to leave work a couple of years ago due to ill health. Her savings meant she qualified for only cb ESA. The savings have now dwindled and are under £6000 limit. She is also on PIP- ER Daily living and ER Mobility. She also has an interest only mortgage which she is struggling to pay. She will benefit from moving to IRESA- she can have disbility premium and SMI, but will reporting achange of circumstances trigger a UC claim in the live service area ?

https://www.rightsnet.org.uk/forums/viewthread/11598/

In most cases should stay on “old style” ESA, with a superseding decision to allow income-related top-up as soon as capital low enough.

Only realistic exception would be where the claimant was already in a full service UC area when they claimed ESA, in which case it is the new style contribution-based only benefit.