What is the simplified explanation of the four scenarios that are excluded from the rule "Ijtihad is not overturned by ijtihad," as mentioned in Al-Suyuti's book "Al-Ashbah wa Al-Nadha'ir," and are there any written or audio commentaries available for these rules?

The jurists' saying, "The Imam has the right to establish a ḥimā (protected area), and if those who come after him wish to annul it, they may do so, according to the more correct opinion, because it is for the public interest, and that interest may change," means that the Imam has the right to designate a specific area for public welfare. It is permissible for those who succeed him to revoke this designation if the interest changes. However, if properties are divided by lot and then an error or injustice is proven, the division is annulled, even if it resulted from a prior ijtihād (independent reasoning). If something is appraised and then new characteristics appear that alter its value, the first appraisal becomes void. In the case of a dispute over real estate ownership, if the judge rules in favor of the claimant who is not in possession due to the defendant lacking evidence, and then the defendant later presents evidence, the first ruling is revoked, and the ruling is reinstated in favor of the one in possession.