All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
It is not strange that there are different narrations from a given Imaam about a specific issue. It is most likely that the reason is due to the Imaam getting to know the preponderant opinion on the issue which is different from his first opinion. This is because the Imaams sought the truth and whenever they found it, they acted upon it and said it. Indeed, it is confirmed that one of the Imaams, who was Imaam Abu Haneefah said to one of his students: "Do not write everything I say, as I might say something today and withdraw it tomorrow." The different narrations could also be due to other reasons.
Therefore, the matter is as you read in the previous Fatwa that there are two narrations of Imaam Ahmad about the issue of divorcing before the marriage contract takes place.
As regards the Shaafi'ee School of jurisprudence, they only have one opinion about this issue, which is that divorce does not take place. Indeed, Imaam Ash-Shaafi'ee himself said in his book entitled Al-Um: "If a man says: "Every woman I will marry is divorced", or mentioned a specific woman, or says to a slave "if I own you, you are free", and then he marries or owns the slave, he is not required to do anything and no ruling applies to him, because the statement which implies a ruling took place when he was not married or owned the slave, so his statement is void."
Finally, it should be noted that whoever does not have a good grasp of religious knowledge by which he may understand the statements of the Imaams and find out the most preponderant among their opinions, then he should ask the scholars whom he trusts (regarding their knowledge and piety) and act upon what they say.
Allaah Knows best.