From my reading of the question, the premise is: You drop everything at once, and you can't further interact in the future (such as waiting for the date to give

From my reading of the question, the premise is: You drop everything at once, and you can't further interact in the future (such as waiting for the date to give the password). They want to know how (if) something, by its very nature, could only possibly be decrypted after a certain date.