The Prophet ﷺ used to perform itikaf for ten days every year. In the year of his death, he performed itikaf for twenty days. The Quran was reviewed with him once every year, but in the year of his death, it was reviewed with him twice.
حدثنا هناد بن السري حدثنا أبو بكر بن عياش عن أبي حصين عن أبي صالح
كان النبي ﷺ يعتكف كل عام عشرة أيام فلما كان العام الذي قبض فيه اعتكف عشرين يوما وكان يعرض عليه القرآن في كل عام مرة فلما كان العام الذي قبض فيه عرض عليه مرتين
Bukhari recorded it in "Itikaf," chapter "Itikaf in the middle ten days of Ramadan," no. 2044, 4998, from the hadith of Abu Bakr bin Ayyash, transmitted through him, and the following hadith serves as a corroborating witness for it.