Perhaps your group or organization has already had a long meeting when a member rises and wants to make a motion. Or the motion itself is controversial and you sense that this would not be a good time to be discussing it. Not that it's a matter that needs to be referred to a committee, it's just that the next meeting would be better — members might be more receptive, or those who would speak for or against the motion could be on hand. This is the time to make a motion to postpone to a certain time. Decide the time this motion should be postponed to before you rise to make the motion.

Postpone to a certain time needs a second and is debatable.