Here are the two postmarks available: 
The pictorial measures 2.68″x1.25″. Also available: 
The dimensions were not given, but the standard “killerbar” postmark is approximately 3.25″x1.00.
The address to send cancellation requests for these is:
USPS SFS Cancellation Services – Presidential Inauguration
8300 NE Underground Drive, Ste 300
Kansas City, MO 64144-9900
From the USPS: “Please be sure to include cancellation instructions for your request so we are sure of which postmark you would prefer. As always, the first 50 cancellations are free, if you have more than 50 cancellations there will be a fee of 5¢ per cancel assessed.”
Where did you get this information? I can’t find any mention of new release on USPS, I’ve talked the USPS customer service, emailed the fulfillment center and two postmasters who have no information either. Not saying you’re wrong. I’m delighted that someone found some real information I just would like to have a copy of the press release or postal notice.
The information was sent to registered dealer/servicers by USPS Cancellation Servicers.