The keyword term "until September 11th" is an adverbial prepositional phrase. Its grammatical function is to modify a verb, an adjective, or another adverb by specifying a terminal point in time for an action, state, or condition.
This phrase is composed of the preposition "until," which establishes a temporal boundary, and its object, the noun phrase "September 11th," which serves as the specific endpoint. As an adverbial, the entire phrase answers the question "when?" or "for how long?" in relation to the clause it modifies. For example, in the sentence "The program will run until September 11th," the phrase modifies the verb "run" by defining the duration of the action.
Identifying this phrase as adverbial is the main point because its function is to set the temporal framework for the subject matter. It signals that the information presented is confined to the period leading up to that specific date. This classification is crucial for interpreting the scope and context of the article, as it dictates that the state of affairs being described ceases or changes on September 11th.
