4 – Discharging the duty of any outstanding obligatory fasts
It was narrated that Abu Salamah said: I heard ‘Aa’ishah (may Allaah be pleased with her) say: I would owe fasts from the previous Ramadaan and I would not be able to make them up except in Sha’baan. Narrated by al-Bukhaari (1849) and Muslim (1146).
Al-Haafiz Ibn Hajar (may Allaah have mercy on him) said:
From her keenness to do that in Sha’baan it may be understood that it is not permissible to delay making them up until another Ramadaan begins. Fath al-Baari (4/191).