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general::
Phrase(s): (Good-bye) until then. [and] (Good-bye) till then.; (Good-bye) till later.; (Good-bye) until later.
Good-bye until sometime in the future. • Sally: See you tomorrow. Good-bye until then. Sue: Sure thing. See you. • Mary: See you later. Bob: Until later. • The announcer always ended by saying, "Be with us again next week at this time. Good-bye until then."
McGrawhill's American Idioms And Phrasal Verbs