Glover ordered work started on the new special delivery stamp on March 13, 1922. This would mark the beginning of a revamping of all the country’s postage stamps. A die was completed and a proof of it was approved by Postmaster General Hubert Work on June 20. Four flat press printing plates were ready for the first run of the stamp on July 7. By the time this stamp was replaced by a more economical rotary press stamp (Scott E15) in late 1927, more than 332 million copies of it had been issued.