Employed Disabled Single Person - What's the Point?

A bit of background:
My daughter, 32 , has been in receipt of Disability Benefits since the age of 8, (DLA - indefinite award, moved over to PIP in 2017 with a 5 year award, enhanced for both living and mobility and an assessors note that things are unlikely to change!).

UC:
She is currently working a 32 hour week, a low waged, somewhat menial job - but she does work and takes great pride in doing so.
She receives Working Tax Credits, (with the SDP). Under forced migration to UC she will be £400 per month worse off once the transition payment is stopped - I'm not sure what the time frame is here, all I've read is that it will be phased out.

I completed one of the benefit calculators on her behalf and note that all they want to know is that another adult is in the household who must be earning as they, (me), are not claiming any 'out of work benefits' - I'm not sure how this is justified, she lives at home with myself and her father, who is himself in the Contributory ESA Support Group - due to long term impact from a severe stroke some 3 years ago. I claim Carers Allowance and work a few hours a week from home on a self employed basis, I am no longer a tax payer as I am not able to put the hours in, (virtually a full time carer) - but bring enough in to keep our heads above water and prevent us having to totally swallow up the last of our depleted savings and claim benefits as a married couple.

PIP:
We received a letter in January 2021, advising that her 5 year award, due to run out in March '23, would be extended until December '23.
The review papers were sent out in January '23, completed and posted back in February, (24hr tracked). I followed this up with more supporting evidence - copies of paperwork supplied by her workplace Occupational Therapist and Management Team last month.
Thanks to the contributors on this site I had read that some claimants seem to be receiving text updates advising claim progression - as we'd had no updates nor acknowledgement/s I rang and was told, "don't worry, we've received both the review and all of the extra evidence and that her paperwork was 'in the queue'." I did ask when this was likely to be ie "where are we in the queue?" and was told, "don't worry, if we haven't got to your daughters paperwork within 5 weeks of her end date we'll send out another extension letter."

Treatment of claimants is appalling - I consider myself an educated person, I used to be employed by Customs and Excise, VAT - when we had backlogs staff would be paid overtime, working a 7 day week to ensure that we continued to rake the money in Later in life I retrained in Health & Safety, I've carried out many audits and Investigations - reports have to be spot on with detail - but filling out an accident investigation form for the HSE is a breeze compared to the PIP and ESA Forms!

I cannot for the life of me see where all of this is 'encouraging the disabled to leave their couches and get a job' (paraphrasing here). I'm beginning to understand why people just throw their hands up in the air and just give up/stay at home, once our savings are depleted sufficiently I'm not at all sure that we'd be much worse off as a family, we could stop working altogether and just jump on the supposed bandwagon! (apologies for the rant - It's now 3am, I've been caring for my daughters night time needs since 1am and felt the need to vent!)

Good luck to all out there, keep reading the guides and wonderful advice on here x

Could one of the mods confirm the definition of 'household' for UC as it is quite confusing. Are the parents one 'household' and the daughter, as she is over 19, a separate 'household'.

Many thanks for your feedback BIS, plus side, my daughter is happy in her own world - early night tonight for me!

Dear Sheila, I hope you feel a tad better for knowing that I really sympathise and was happy to read all your venting.
May I take a turn to add mine? Motability have wasted about ten phone hours over three days pretending to be nice while leaving us carless therefore trapped in the house with only what supplies we have or can order or beg neighbours to get for us. We have fallen through the gaps between them and their old and new insurers after our old car was written off [no-fault] before the new one was built. Hoping for better news tomorrow.
D.