permissible to delay making up the fasts until another Ramadan. Here, Ramadan must take nunation, because it is indefinite: it does not refer to a particular Ramadan, as indicated by the word “another.” The addition of alif and nun does not render a word diptote unless it is coupled with either proper-name status or adjectival usage; here, it is neither a proper name nor an adjective.
The general rule is that any word whose being diptote depends on its being a proper name is declinable when it is indefinite.
The word “another” is diptote because of its adjectival nature and its irregular form.
It is understood from the author’s words that one may delay the make-up fasts until only the equivalent number of days remains in Sha'ban. This is due to his statement, “and it is not permissible [to delay them] until another Ramadan”: thus, one may make them up in any month, either consecutively or separately, provided that the remaining days of Sha'ban are not equal to the number of fasts one owes. If the remaining days of Sha'ban equal the number one owes, then one must make them up consecutively.
His statement, “without an excuse,” indicates that if one delays them until another Ramadan because of an excuse, this is permissible—for example, if one is travelling and the journey continues, or is ill and the illness continues; or if a woman is pregnant and her pregnancy continues, or is nursing and needs to break the fast throughout the entire year. For if breaking the fast is permissible because of these excuses during Ramadan itself, when the fast is being observed at its appointed time, then its permissibility during the days of make-up fasting is all the more evident.
In his statement, “and it is not permissible [to delay them] until another Ramadan without an excuse,” the author did not address fasting before making up the missed fasts. Is it permissible to fast before making them up, and would such a fast be valid if one did so?
The answer is that if the fast is obligatory, such as an expiation or a compensatory fast, there is no harm in it. But if it is a voluntary fast, then according to the authoritative position of the school, voluntary fasting before making up the missed fasts is invalid, and one is sinful.