It’s not an exact science, but generally when the person stops eating or drinking, the end is near. My mother was given two weeks when her cancer metastasized to her abdominal cavity and developed ascites - it was about 10 days later when she passed. The last 24 hours it was clear she was actively dying. If an experienced hospice provider indicates death is near, they are probably right - though there will always be exceptions.

In my experience with dad and FIL, very accurate. The hospice staff and nurses know the signs.

In our case, the hospice nurse in MoCo injected a lethal dose of morphine into my parent and told my sister "it won't be long." None of us were with the parent. She found my dad on a couch at assisted living where he must have wheeled himself to try and get help...

She got him to the hospital and they gave him Naloxone. But the damage was done.

The law said if he didn't eat a meal in assisted living that he had to be on hospice. And then that allowed hospice to remove all his medications and to give him lethal doses of morphine.

After that, we would not let hospice anywhere near him.