Depends on the phone call but I find “later” usually means “tomorrow or later”

15

Later is subjective. Your “later” might be an hour whereas another person’s might be “the next time I think about you, or “the next time I have a few minutes in my schedule.” If you need/want an objective time then clarify it! They can’t read your mind just like you can’t read theirs. You could say something like “how much later?” Or even “hey do you mind if we set a time because I don’t want to get busy and miss your call.”

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