The phrase "more overnight" implies an increase or growth that occurs quickly, usually within a short period of time. The antonyms for this phrase would be "less," "decrease," or "shrinking." If something is becoming "less overnight," it is actually decreasing in size or quantity, rather than growing. Similarly, if something is "shrinking overnight," it is getting smaller, rather than getting larger. While "more overnight" suggests rapid growth or progress, the antonyms suggest a slower, more gradual change. Understanding these antonyms can help us describe and understand changes in a variety of contexts.