Humorous way of saying, "My request is totally non-urgent; I'm just asking if you could please perform this action when it's convenient for you."
Just like the independent/cautious-minded Angus MacGyver (in one of his TV episodes, he grimly remarked, "When someone assuredly tells me not to worry, THAT'S when I START WORRYING!"), anytime someone begins an assistance-request with, "Sometime in the next millennium...", I get nervous, since in all probability it's gonna be an exceptionally difficult/arduous/boring task that they're asking me about, and/or the undertaking may actually be a lot more urgent than even the requester realizes.
by QuacksO September 19, 2018
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