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after this; from now on; hereafter
thereafter; since (then); after
已後のことは改めて連絡します。
I will contact you again about what comes after.
入社已後、一度も遅刻したことがない。
I have never been late once since joining the company.
明治已後に日本は急速に近代化した。
Japan modernized rapidly after the Meiji era.