Originally Posted by Karnak

A signed FDRA means we accept an FDP extension just as much as a signed FDRA means we accept the fuel load.

If something that affects the flight changes, the captain alters it…or doesn't proceed.

To assume anything else is silly. If a volcano erupts along your route, and you want more fuel to go around it, do you simply suck it up because you've signed an FDRA with a fuel load? If you wrench your back while shifting bags in the cockpit, do you ignore the injury because you've signed an FDRA with a statement about physical status?

Any captain that believes a signed FDRA can't be voided by evolving circumstances probably shouldn't be a pilot in command at Delta.