The Messenger of Allah ﷺ fasted more in Shaban than in any other month of the year, for he would fast it in its entirety.
حدثنا سويد بن عمرو قال حدثنا أبان حدثنا يحيى عن أبي سلمة
كان أكثر صوم رسول الله ﷺ من شهر من السنة من شعبان فإنه كان يصومه كله
Its chain of transmission is sahih. It was mentioned previously in 24986.