There is a difference in the offense if the license holder fails to depart, but not a defense against prosecution.
https://statutes.capitol.texas.gov/Docs ... /PE.30.htm
30.06 (d) and 30.07 (d) both read:
(d) An offense under this section is a Class C misdemeanor punishable by a fine not to exceed $200, except that the offense is a Class A misdemeanor if it is shown on the trial of the offense that, after entering the property, the license holder was personally given the notice by oral communication described by Subsection (b) and subsequently failed to depart.