Is it permissible to delay fasting for an atonement for an oath (kaffarat al-yameen) until the intense heat subsides?

The expiation for an oath is feeding ten poor people, or clothing them, or freeing a slave. If one cannot find [the means], then fasting for three days. The expiation becomes immediately due upon breaking the oath, and it is not permissible to delay it as long as the person is able. However, if immediate fulfillment leads to excessive hardship, such as fasting in intense heat, then delay is permissible until the hardship ceases, based on the opinion of those who hold that expiation is on a relaxed timeline, and by analogy with the permissibility of delaying Zakat (definition) for a need or benefit.