Updated June 1st: First day postmarks:
Standard 4-bar FIRST DAY OF ISSUE
Digital Color Postmark:

from the Postal Bulletin May 27th:
On June 1, 2015, in Kansas City, MO, the U.S. Postal Service® will issue the Penguins additional ounce rate stamp, (Non-denominated priced at 22 cents), in one design, in a pressure-sensitive adhesive (PSA) coil of 100 stamps (Item 786200) and also a pane of 20 stamps (Item 117700).

The stamp will go on sale nationwide June 1, 2015.

This stamp from the U.S. Postal Service pays tribute to the majestic emperor penguin (Aptenodytes forsteri). Largest of the penguin species, the emperor stands over three feet tall and can weigh more than 80 pounds. Emperor penguins dive beyond 1,500 feet — deeper than any other bird. The stamp art is a stylized drawing of a pair of emperor penguins on a cool green background. The pop of orange and yellow on the birds’ beaks and ear patches lends a regal look to the aptly named emperors. Art director Carl Herrman designed the stamp, which was illustrated by Nancy Stahl. The words “ADDITIONAL OUNCE” on this stamp indicate its usage value. Like a Forever® stamp, this stamp will always be valid for the rate printed on it. The initial price and value for this stamp is 22 cents.

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 http://www.usps.com/shop, or by calling 800-STAMP-24. 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:

22¢ Penguins Stamp
Cancellation Services
8300 NE Underground Drive, Pillar 210
Kanas City, MO 64144-0001

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. For more than 50, customers have to pay five cents each. All orders must be postmarked by July 31, 2015.

There are two philatelic products for the Penguins PSA coil of 100 stamps issue:

• 786216, First-Day Cover, (plus 1 Winter Fun Random), $1.15.
• 786221, Digital Color Postmark (plus 1 Winter Fun Random), $1.86.

There are seven philatelic products for the Penguins pane of 20 stamps issue:

• 117706, Press Sheet with Die-cut, $44.00 (print quantity 250).
• 117708, Press Sheet without Die-cut, $44.00 (print quantity 500).
• 117710, Digital Color Postmark Keepsake, $6.95.
• 117716, First-Day Cover, (plus 1 Winter Fun random), $1.15.
• 117721, Digital Color Postmark, (plus 1 Winter Fun random), $1.86.
• 117731, Stamp Deck Card, $0.95.
• 117732, Stamp Deck Card with Digital Color Postmark, (plus 1 Winter Fun random), $2.21.

Technical Specifications:

Issue: Penguins Stamp (coil)
Item Number: 786200
Denomination & Type of Issue: Additional Ounce Rate Non-Denominated, Mail-Use
Format: Coil of 100 (1 design)
Series: N/A
Issue Date & City: June 1, 2015, Kansas City, MO 64108
Art Director: Carl T. Herman, Carlsbad, CA
Designer: Carl T. Herman, Carlsbad, CA
Typographer: Carl T. Herman, Carlsbad, CA
Artist: Nancy Stahl, New York, NY
Modeler: Donald Woo
Manufacturing Process: Offset, Microprint
Printer: Banknote Corporation of America/SSP
Printed at: Browns Summit, NC
Press Type: Alprinta 74
Stamps per Coil: 100
Print Quantity: 200 million stamps
Paper Type: Phosphor Tagged Paper, Overall
Adhesive Type: Pressure-sensitive
Processed at: Banknote Corporation of America, Browns Summit, NC
Colors: Cyan, Magenta, Yellow, Black
Stamp Orientation: Vertical
Image Area (w x h): 0.73 x 0.84 in./18.54 x 21.33 mm
Stamp Size (w x h): 0.87 x 0.98 in./22.09 x 24.89 mm
Plate Size: 775 stamps per revolution
Plate Numbers: “S” followed by four (4) single digits
Coil Number Frequency: Plate numbers every 31st stamp below stamp image

Technical Specifications:

Issue: Penguins Stamp (pane)
Item Number: 117700
Denomination & Type of Issue: Additional Ounce Rate Non-Denominated, Mail-Use
Format: Pane of 20 (1 design)
Series: N/A
Issue Date & City: June 1, 2015, Kansas City, MO 64108
Designer: Carl T. Herrman, Carlsbad, CA
Art Director: Carl T. Herrman, Carlsbad, CA
Typographer: Carl T. Herrman, Carlsbad, CA
Artist: Nancy Stahl, New York, NY
Modeler: Donald Woo
Manufacturing Process: Microprint, Offset
Printer: Banknote Corporation of America/SSP
Printed at: Browns Summit, NC
Press Type: Alprinta 74
Stamps per Pane: 20
Print Quantity: 120 million stamps
Paper Type: Phosphor Tagged Paper, Overall
Adhesive Type: Pressure-sensitive
Processed at: Banknote Corporation of America, Browns Summit SC
Colors: Cyan, Magenta, Yellow, Black
Stamp Orientation: Vertical
Image Area (w x h): 0.73 x 0.84 in./18.54 x 21.33 mm
Overall Size (w x h): 0.87 x 0.98 in./22.10 x 24.89 mm
Full Pane Size (w x h): 5.35 x 4.93 in./135.89 x 125.22 mm
Press Sheets Size (w x h): 10.6 x 24.4 in./269.24 x 619.76 mm
Plate Size: 200 stamps per revolution
Plate Numbers: “S” followed by four (4) single digits
Marginal Markings: Front: Plate numbers in four corners of pane
Back: © 2015 USPS • USPS logo • Plate position diagram • Barcode (117700) in upper right and lower left corners of pane • Promotional text

From the USPS May 26th:

This additional ounce stamp pays tribute to the majestic emperor penguin (Aptenodytes forsteri). Largest of the penguin species, the emperor stands over 3 feet tall and can weigh more than 80 pounds. Emperor penguins dive beyond 1,500 feet — deeper than any other bird. The stamp art is a stylized drawing of a pair of emperor penguins on a cool green background. The pop of orange and yellow on the birds’ beaks and ear patches lends a regal look to the aptly named emperors. Art director Carl Herrman of Carlsbad, CA, designed the stamp, illustrated by Nancy Stahl of New York City. The words “ADDITIONAL OUNCE” on this stamp indicate its usage value. These Forever stamps will always be equal in value to the applicable price for the price category at the time of use. The initial price and value for this stamp is 22 cents, effective May 31.

From the USPS May 18th:
This stamp from the U.S. Postal Service pays tribute to the majestic emperor penguin (Aptenodytes forsteri). Largest of the penguin species, the emperor stands over three feet tall and can weigh more than 80 pounds. Emperor penguins dive beyond 1,500 feet—deeper than any other bird. The stamp art is a stylized drawing of a pair of emperor penguins on a cool green background. The pop of orange and yellow on the birds’ beaks and ear patches lends a regal look to the aptly named emperors. Art director Carl Herrman designed the stamp, illustrated by Nancy Stahl. The words “ADDITIONAL OUNCE” on this stamp indicate its usage value. These Forever stamps will always be equal in value to the applicable price for the price category printed on the at the time of use. The initial price and value for this stamp is 22 cents.

The first day of issue is June 1, without a ceremony. The city is Kansas City (Stamp Fulfillment Services).

Updated June 1st: First day postmarks:
Standard 4-bar FIRST DAY OF ISSUE
Digital Color Postmark:

from the Postal Bulletin May 27th:
On June 1, 2015, in Kansas City, MO, the U.S. Postal Service® will issue the Eastern Tiger Swallowtail Non-machineable Surcharge Rate, (Non-denominated priced at 71 cents), in one design, in a pressure-sensitive adhesive (PSA) pane of 20 stamps (Item 117800).

The stamp will go on sale nationwide June 1, 2015.

The U.S. Postal Service celebrates the Eastern Tiger Swallowtail on its fifth butterfly stamp issuance for greeting card envelopes that require additional postage. The stamp art is a colorful, highly stylized depiction of the butterfly. The words “NON-MACHINEABLE SURCHARGE” on the stamp indicate its usage value. Like a Forever® stamp, this stamp will always be valid for the rate printed on it. The initial price and value for this stamp is 71 cents. Named for the black “tiger” stripes along the upper surfaces of its wings, the Eastern Tiger Swallowtail is easily spotted. Abundant from southern New England to Florida and west to the Great Plains and central Texas, the Eastern Tiger Swallowtail is a frequent visitor to gardens, woodlands, and riverbeds. Tom Engeman was the artist. Art director Derry Noyes designed the stamp.

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 http://www.usps.com/shop, or by calling 800-STAMP-24. 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:

71¢ Eastern Tiger Swallowtail Stamp
Cancellation Services
8300 NE Underground Drive, Pillar 210
Kansas City, MO 64144-0001

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. For more than 50, customers have to pay five cents each. All orders must be postmarked by July 31, 2015.

There are seven philatelic products for the Eastern Tiger Swallowtail stamp issue:

• 117806, Press Sheet with Die-cut, $85.20 (print quantity 250).
• 117808, Press Sheet without Die-cut, $85.20 (print quantity 500).
• 117810, Digital Color Postmark Keepsake, $16.95.
• 117816, First-Day Cover, $1.15.
• 117821, Digital Color Postmark, $1.86.
• 117831, Stamp Deck Card, $0.95.
• 117832, Stamp Deck Card with Digital Color Postmark, $2.21.

Technical Specifications:

Issue: Eastern Tiger Swallowtail Stamp
Item Number: 117800
Denomination & Type of Issue: Non-Machineable Surcharge Rate, Mail-Use
Format: Pane of 20 (1 design)
Series: N/A
Issue Date & City: June 1, 2015, Kansas City, MO 64108
Designer: Derry Noyes, Washington, DC
Art Director: Derry Noyes, Washington, DC
Typographer: Derry Noyes, Washington, DC
Artist: Tom Engeman, Frederick, MD
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: 100 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, PMS 2726C Purple
Stamp Orientation: Vertical
Image Area (w x h): 1.09 x 1.09 in./27.56 x 27.56 mm
Overall Size (w x h): 1.23 x 1.23 in./31.12 x 31.12 mm
Full Pane Size (w x h): 5.90 x 7.12 in./149.86 x 180.85 mm
Press Sheet Size (w x h): 11.80 x 21.36 in./299.72 x 542.54 mm
Plate Size: 240 stamps per revolution
Plate Numbers: “P” followed by five (5) single digits
Marginal Markings: Front: Plate numbers in four corners of pane
Back: © 2015 USPS • USPS logo • Plate position diagram • Barcode (117800) in upper right and lower left corners of pane • Promotional text

From the USPS May 26th:
The U.S. Postal Service celebrates the Eastern tiger swallowtail on its fifth butterfly stamp issuance for greeting card envelopes that require additional postage. The stamp art is a colorful, highly stylized depiction of the butterfly. The words “NON-MACHINEABLE SURCHARGE” on the stamp indicate its usage value. Non-machinable items require sorting by hand. This stamp also may be used for mailing items weighing up to 2-ounces.

These Forever stamps will always be equal in value to the applicable price for the price category printed on them, at the time of use. The initial price and value for this stamp is 71 cents, effective May 31. Named for the black “tiger” stripes along the upper surfaces of its wings, the Eastern tiger swallowtail is easily spotted. Abundant from southern New England to Florida and west to the Great Plains and central Texas, the Eastern tiger swallowtail is a frequent visitor to gardens, woodlands, and riverbeds. Tom Engeman of Frederick, MD, was the artist. Art director Derry Noyes of Washington, DC, designed the stamp.

[Note “This stamp also may be used for mailing items weighing up to 2-ounces.” in the above writeup. —LdeV]

From the USPS May 18th:
The U.S. Postal Service celebrates the Eastern tiger swallowtail on its fifth butterfly stamp issuance for greeting card envelopes that require additional postage. The stamp art is a colorful, highly stylized depiction of the butterfly. The words “NON-MACHINEABLE SURCHARGE” on the stamp indicate its usage value. These Forever stamps will always be equal in value to the applicable price for the price category printed on them, at the time of use. The initial price and value for this stamp is 71 cents. Named for the black “tiger” stripes along the upper surfaces of its wings, the Eastern tiger swallowtail is easily spotted. Abundant from southern New England to Florida and west to the Great Plains and central Texas, the Eastern tiger swallowtail is a frequent visitor to gardens, woodlands, and riverbeds. Tom Engeman was the artist. Art director Derry Noyes designed the stamp.

The first day of issue is June1, without a ceremony. The city is Kansas City (Stamp Fulfillment Services).