Is it permissible to fast the White Days and the Day of 'Arafah with the intention of supererogatory (nafl) fasts, while I owe many days of make-up (qada') fasts?

One must make up for missed days of Ramadan (definition), as Allah the Almighty says: "But whoever is ill or on a journey, then [he must make up] an equal number of other days." Making up these days is not obligatory immediately, nor is continuity a condition, unless there remains in Sha'ban only enough time to make them up. Whoever delays making them up until the next Ramadan without a valid excuse is sinful and must make them up along with an expiation of feeding one poor person for each day. If one begins fasting a day with the intention of making up a missed fast, it is not permissible to break it without a valid excuse. For one who fasts the recommended days with the sole intention of making up missed fasts, it is hoped that they will receive a reward similar to that of fasting those days. However, it is preferable, as a precaution, not to combine the intention of a voluntary fast with the intention of a make-up fast.