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belatedly; though a little too late
遅ればせながら、お誕生日おめでとう！
Belated happy birthday!
遅ればせながら、新サービスを開始いたします。
Belatedly, we are pleased to announce the launch of our new service.
遅ればせながら、ご結婚心よりお祝い申し上げます。
Belatedly, I extend my heartfelt congratulations on your marriage.