“[T]he State in its sovereign capacity, unlike ordinary litigants, is not subject to the defenses of limitations, laches, or estoppel.” E.g., State v. Durham, 860 S.W.2d 63 (Tex. 1993). The Supreme Court identified an exception to that general principle in Wallace v. Tex. Dept. of Fam. Prot. Servcs., No. 17-0428 (Oct. 25, 2019) (and two companion cases), holding: “We agree that the trial court lacked jurisdiction because Wallace did not seek rehearing of the order she challenges before the administrative law judge. But because, as in Mosley, the agency misrepresented the proper procedure for judicial review in a letter to Wallace, we hold that Wallace was denied due process.”