I say, and with God's success: If one renounces Islam, the retreat is invalidated by their renunciation, and they do not build upon what has passed, nor is there any obligation to make up for the required retreat if they return to Islam; as Allah, the Exalted, says: {Say to those who disbelieve, if they cease, what has passed will be forgiven for them} Al-Anfal: 38, and His Prophet (peace be upon him) said: «Islam wipes out what came before it» in Musnad Ahmad 4: 198, and Allah knows best.