What is the ruling regarding a woman who missed days of fasting in Ramadan due to menstruation and was late in making them up until Sha'ban, given her inability to feed a poor person for each day?

Fasting is not permissible during menstruation, and the missed days must be made up after Ramadan. If you were unaware of the impermissibility of delaying (the make-up fast), then there is no expiation upon you. However, if you were aware, then you must feed a poor person for each day you delayed making it up. If you are unable to do so, the expiation remains an obligation upon you. The Malikis hold that there is no expiation upon you if you were excused for the delay due to menstruation, and this is a strong opinion.