Anchor start of fades

I often want to set a fade to start from a particular point in an event, say the last note of a phrase. But when I then find I have to adjust the event length, the whole fade moves with it and I have to reset it. There may be rather a lot to do, so could there be a way of keeping the start of the fade in position while stretching/shrinking the fade with the event length.

Maybe this could be done with a mod-key when resizing normally.