If a person breaks his fast in Ramadan for an excuse, is he required to abstain for the rest of the day if his excuse is removed?

The questioner : May Allah do you good. If a person ate at the beginning of the day in Ramadan while intending to break the fast, or if people [were breaking their fast], and then he continued until the performance of Maghrib?

The Shaykh : Because he should fast what is due from him, completing the fast, and there is nothing upon him.

The questioner : No, he does not continue eating, I mean.

The Shaykh : No, it is not permissible. As long as he has been excused, his fasting is... what? Valid. And in that case, he does not break his fast.

The questioner : For the whole day.

The Shaykh : For the whole day, and the stick is over his head? In any case, if this person wants to eat all day, wants to go to his belly, do not pose questions that make people laugh. A student of knowledge does not pose such wretched questions. However, if a person breaks his fast for an excuse other than coercion, because coercion does not break the fast, but if a person breaks his fast for a legal excuse, he should not break his fast for the rest of the day.
Did you understand? An example of this is a person who was compelled to drink due to severe thirst. We said, "Open it up." We tell you to eat for the rest of your day.
And it is not obligatory for the person. And this is a rule: everyone who breaks his fast at the beginning of the day for a legal excuse, let him eat for the whole day. For this reason, the author of al-Mughni mentioned from Ibn Mas'ud (may Allah be pleased with him) that he said: "Whoever eats at the beginning of the day, let him eat at the end of it."
And there are examples of this, such as a traveler who arrives in the town during the day before the prayer or after the prayer. Is he required to abstain or not? No, it is not required of him, because the man broke his fast at the beginning of the day for a legal excuse.
What benefit is there for him if he abstains? No benefit. For this reason, the scholars (may Allah have mercy on them) posed a riddle in this matter. They said: If a traveler arrives while breaking his fast and finds that his wife has become pure from menstruation during the day, he may have intercourse with her, in the same town. And they said: A mature, sane man has intercourse with his wife during the day of Ramadan while he is in his town. This is a riddle. Its form is this: he arrived in the town from travel while breaking his fast, so he continues in his breaking of the fast. The menstruating woman is breaking her fast at the beginning of the day, so she continues in her breaking of the fast, even if she becomes pure from the prohibition.