The point being the word meaning 24-hour day could also have been used metaphorically to indicate an unknown period of "time" before time.
Day by itself can mean an indefinite period of time, but it can also mean one revolution of the Earth. It all depends on the context.
In the case of Creation Week the word day is further qualified by a particular sentence structure that can mean nothing else but one revolution of the Earth.
Now a person can argue that the account is wrong and be justified, but even many critics who believe that the account is wrong admit that the Hebrew text is talking about a day in the sense of one revolution of the Earth.
It seems to me that it is "grasping at straws" to argue that the intent was to be metaphorical when each time the word is used it is qualified by a sentence structure as if to emphasize the literal meaning of a single Earth day. Why would anyone do that for each of the days if the intent was to be metaphorical?