Does the 'under consideration' stamp on my Thai visa act as a 30-day extension, and how is the duration of my one-year extension calculated?

Went to immigrations yesterday with my wife in Phichit . Submitted all the paperwork for my one year extension, and received my under consideration stamp. My 90 day visa expires on January 31. The immigration officer put a date of March 1 on my under consideration stamp. She said that the, under consideration stamp must be 30 days after the expiration of my visa. So I am assuming that the under consideration stamp is acting like a 30 day extension to my visa. Is that correct? One other question when my one year extension gets approved will it be one year from the date that I applied or one year from the date that it was approved?