[magicalhippo]

It's highly non-linear, as you allude to.

For a mother with a young child, getting another 1.5 years can be the difference between the child not knowing their mother and having some memory of her.

For someone with no or adult children, it can be a lot less significant. My dad passed away from cancer when I was 30 and while I certainly would have taken an extra year with him, it wouldn't have changed much.

[CalRobert]

Nothing like a deadline to make the most of 18 months. I have a 4 and 6 year old and if I were in this situation I'd cherish the hell out of that time. And hope for further improvements in treatment (and a stroke of luck) in the meantime.