previously; beforehand; already; in advance (indicates something existed or was planned before now)
かねてよりご連絡しておりました通り、会議は来週に延期になりました。
As we informed you earlier, the meeting has been postponed until next week.
彼女はかねてよりその計画に反対していた。
She had long been opposed to that plan.
かねてより念願だった留学が実現した。
The study abroad opportunity I had wished for for some time finally came true.