The longest day still asks you to choose what to leave unfinished.

More hours do not remove the necessity of choosing. However much time a day contains, it ends with things undone, and the only real question is whether you selected which ones or let the last hour select for you. Working longer changes the size of the list and not the fact of the list.

Before the day gets away, decide what you are willing to leave. Say it plainly to yourself, and if others are affected, say it to them too. Deciding what will not happen is the part most people skip, and it is the part that makes the rest calm.