Is it permissible to consume oil that has been replaced by olives after learning of the impermissibility of this action, and is expiation due for it?

The majority of jurists hold that it is impermissible to sell olives for oil due to the absence of equivalence, which is a condition for usurious commodities. Abu Thawr dissented from this view, and Sheikh Al-Islam Ibn Taymiyyah adopted his opinion, arguing that anything that ceases to be a staple food through manufacturing is not subject to usury, thus making it permissible to sell oil for olives. This is also the view of the Hanafis if the pure oil is more than the oil extracted from the olives, and the view of the الظاهرية (Zahiris) who restrict usury to the six usurious commodities. There is a narration in the Hanbali school indicating disfavor (كرهة) rather than prohibition. Based on this, it is permissible to rely on the opinion of permissibility in past contracts and transactions.