- As of means based on a specific time.
An example of as of used as a preposition is in the following sentence: "Final papers will be available with grades as of 6 p.m. on December 21st."
as of definition by American Heritage Dictionary
prepositionThe American Heritage® Dictionary of the English Language, 4th edition Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
On; at: The project was terminated as of January 1.
as of - Phrases/Idioms
From, at, or until a given time. For example, As of five o'clock the store will be closed for inventory, or As of last December our meetings have been open to the public, or As of now I'm not sure how I'll vote. This idiom was first used in business but came into more general use. [c. 1900]