What is the ruling on a husband having intercourse with his wife during the daytime in Ramadan ten years ago, and not remembering the number of days he broke his fast?

He who has intercourse with his wife during the daytime in Ramadan, knowingly and intentionally, has disobeyed Allah, and he must repent and offer the major expiation (kaffarah kubra). The expiation is not repeated for multiple instances of intercourse on the same day, as the fast of that day is nullified by the first act of intercourse. Scholars have differed concerning one who repeatedly engages in intercourse on multiple days without offering expiation for the first instance. The majority opinion is that an expiation is required for each day that was nullified by intercourse, and this is the correct view. As for one who has offered expiation for the first day and then has intercourse on another day, another expiation is incumbent upon him, without any difference of opinion.