You have written that you have been sending in sick notes since March 2024, is that correct?
I am currently also navigating the mess that is ESA, it’s taken them 6 weeks just to send out a capability questionnaire to me, when I phoned to question it a few weeks ago I was told they are running behind and it would be 5 weeks, not the 14 days they advise on the initial application. The conspiracy theorist in me thinks it’s a deliberate move to save money as some people will probably abandon their claim if they meanwhile get better and are able to work again in that time frame. It would be interesting to know how many claims are abandoned, but I am digressing.
Back to the point, the advisor also reassured me that my claim would be fully backdated if it was successful and I continued to send in fit notes. I have checked my HMRC PAYE records and they have already put themselves on my tax account and I can see a date my claim will presumably start on there. Maybe this is something you might want to check too?
If this is leaving you financially distressed get back in touch with them as I think they can offer a loan to be paid back out of your claim? Also, depending on what your diagnosis is, it may be worth seeking out a charity associated with your diagnosis, as they may have their own benefits advisors to help you.
I was told to have someone with me for support when I have my health assessment interview, apparently it can be a bit brutal; the anecdote I was told, by another patient in oncology, is that the interview was on the telephone, lasted over two hours (!), the questions asked were repetitive as though designed to catch you out and it only stopped when the person’s husband stepped in to say enough, she is exhausted. She has said when it runs out she won’t re-apply as she can’t go through it all again. She was a professional woman, genuinely ill with a chronic, life limiting diagnosis and it’s shocking that she feels she cannot face a claim for financial help again.
Anyway, hoping my answer will bump you back up the board and someone more knowledgeable can help you (and me!).
Would also like to hear some anecdotes where it isn’t anxiety inducing to apply! I’ve got enough to worry about without this too.