Permission to separate make-up days is not an encouragement to postpone them indefinitely without a reason. Once the excuse has ended, prompt fulfilment is preferable.
Legally acceptable scheduling and good practice in promptly discharging a debt of worship are separate questions.
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Kitab al-Sawm: Illness, Travel, Make-up Fasts and Delayed Qaḍāʾ
Permission to separate make-up days is not an encouragement to postpone them indefinitely without a reason. Once the excuse has ended, prompt fulfilment is preferable.
Legally acceptable scheduling and good practice in promptly discharging a debt of worship are separate questions.