Updated May 14th: Here is the first day Digital Color Postmark: It measures 2.995” x 1.5”. There is no B&W pictorial for this issue, but there is a “special” postmark that individual post offices may use: Updated May 11th, from the Postal Bulletin:
On June 7, 2016, in Indianapolis, IN, the U.S. Postal Service® will issue the Indiana Statehood stamp (Forever® priced at 47 cents) in one design, in a pressure-sensitive adhesive (PSA) pane of 20 stamps (Item 473700).

The stamp will go on sale nationwide June 7, 2016.

This stamp celebrates the 200th anniversary of Indiana’s statehood. Known as the Hoosier State, Indiana became the 19th state of the Union on December 11, 1816. The stamp features a contemplative photograph of the expansive cornfields near Milford, Indiana. The photographer, Michael Matti, grew up in Milford and had driven past that view hundreds of times until one day he decided to pull over, stand on top of his car, and take in the beautiful sunset. Art director Derry Noyes designed the stamp with Matti’s existing photograph.

Initial Supply to Post Offices: Stamp Fulfillment Services will make an automatic push distribution to Post Offices™ of a quantity to cover approximately 30 days of sales.

How to Order the First-Day-of-Issue Postmark:
Customers have 60 days to obtain the first-day-of-issue postmark by mail. They may purchase new stamps at their local Post Office, at The Postal Store® website at www.usps.com⁄shop, or by calling 800-782-6724. They should affix the stamps to envelopes of their choice, address the envelopes (to themselves or others), and place them in a larger envelope addressed to:

Indiana Statehood Stamp
Postmaster
125 West South Street
Indianapolis, IN 46206-9998

After applying the first-day-of-issue postmark, the Postal Service will return the envelopes through the mail. There is no charge for the postmark up to a quantity of 50. There is a 5-cent charge for each additional postmark over 50. All orders must be postmarked by August 7, 2016.

There are seven philatelic products for this stamp issue:

• 473706 Press Sheet with Die-cut, $56.40 (print quantity 1,000).
• 473710 Digital Color Postmark Keepsake, $11.95.
• 473716 First-Day Cover, $0.91.
• 473721 Digital Color Postmark, $1.62.
• 473724 Framed Art, $39.95.
• 473730 Ceremony Program, $6.95.
• 473733 Panel, $10.95.

Technical Specifications:

Issue: Indiana Statehood
Item Number: 473700
Denomination & Type of Issue: First-Class Mail Forever
Format: Pane of 20 (1 design)
Series: Statehood
Issue Date & City: June 7, 2016, Indianapolis, IN 46298
Designer: Derry Noyes, Washington, DC
Art Director: Derry Noyes, Washington, DC
Typographer: Derry Noyes, Washington, DC
Existing Photo: Michael Matti
Modeler: Joseph Sheeran
Manufacturing Process: Offset, Microprint
Printer: Ashton Potter (USA) Ltd. (APU)
Printed at: Williamsville, NY
Press Type: Muller A76
Stamps per Pane: 20
Print Quantity: 30 million stamps
Paper Type: Nonphosphored Type III, Block Tag applied
Adhesive Type: Pressure-sensitive
Processed at: Ashton Potter (USA) Ltd. (APU)
Colors: Black, Cyan, Magenta, Yellow
Stamp Orientation: Horizontal
Image Area (w x h): 1.42 x .84 in⁄36.07 x 21.34 mm
Overall Size (w x h): 1.56 x .98 in⁄39.62 x 24.89 mm
Full Pane Size (w x h): 7.24 x 5.95 in⁄183.90 x 151.13 mm
Press Sheet Size (w x h): 21.72 x 11.90 in⁄551.69 x 302.26 mm
Plate Size: 240 stamps per revolution
Plate Numbers: “P” followed by four (4) single digits
Marginal Markings:
Front: Plate numbers in four corners of pane
Back: USPS Logo • UPC Code in upper right and lower left corners of pane • Plate position diagram • 2015 USPS • Promotional text

From the USPS August 20, 2015:

FDOI: 2nd Quarter (Statehood date: December 11, 1816)
Format: Pane of 20

This stamp celebrates the 200th anniversary of Indiana’s statehood. Known as the Hoosier State, Indiana became the 19th state of the Union on December 11, 1816. Indiana has often been considered the heartland of America. Its fertile soil has long made it ideal for crops like corn, which remains a staple of Indiana’s agricultural economy. The state is also known for the Indianapolis 500 and its devotion to the game of basketball.

The stamp features a contemplative photograph of the expansive cornfields near Milford, Indiana, at sunset. The photographer, Michael Matti, grew up in Milford.

Existing Photo: Michael Matti
Art Director: Derry Noyes

Notes: No river? 🙂 Obviously, the stamp will not be issued on the statehood anniversary date. In other states, the bicentennial/centennial commissions have asked for earlier release dates so that the stamps can be used to promote the anniversary celebrations.