The Scott catalogue numbers for this issue:
5317 (50¢) Birds in Winter – Black-capped chickadee
5318 (50¢) Birds in Winter – Northern cardinal
5319 (50¢) Birds in Winter – Red-bellied woodpecker
5320 (50¢) Birds in Winter – Blue jay
a. Block of 4, #5317-5320
b. Convertible booklet pane of 20, 5 each #5317-5320

Updated May 10th: These stamps will be issued Saturday, September 22 in Quechee, VT. Nice catch by member Lefty Dundee: The Vermont Institute of Natural Science is there. Nothing on its website yet.

Updated August 25th:
On September 22, 2018, in Quechee, VT, the U.S. Postal Service® will issue the Birds in Winter stamps (Forever® priced at the First-Class Mail® rate) in four designs, in a pressure-sensitive adhesive booklet of 20 stamps (Item 681900). The stamps will go on sale nationwide September 22, 2018.

The Birds in Winter stamps celebrate four of winter‘s winged beauties:

• The black-capped chickadee (Poecile atricapillus),
• The northern cardinal (Cardinalis cardinalis),
• The blue jay (Cyanocitta cristata), and
• The red-bellied woodpecker (Melanerpes carolinus).

The stamp art highlights the handsome plumage of resident birds often spotted throughout the year‘s coldest months. Evoking the drab feeling of winter with the stark white backgrounds, stamp artist Nadia Taylor hoped to create a vivid contrast with the bright flashes of color found in the digital rendering of each bird. Art director Antonio Alcalá designed the stamps.

Item 681900 Birds in Winter Double-Sided Booklet of 20 Stamps

How to Order the First-Day-of-Issue Postmark:
Customers have 120 days to obtain the first-day-of-issue postmark by mail. They may purchase new stamps at their local Post Office™ or at The Postal Store® website at usps.com/shop. They must affix the stamps to envelopes of their choice, address the envelopes (to themselves or others), and place them in a larger envelope addressed to:

FDOI – Birds in Winter Stamps
USPS Stamp Fulfillment Services
8300 NE Underground Drive, Suite 300
Kansas City, MO 64144-9900

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 January 22, 2019.

Technical Specifications:

Issue: Birds in Winter Stamps
Item Number: 681900
Denomination & Type of Issue: First-Class Mail Forever
Format: Double-Sided Booklet of 20 (4 designs)
Series: N/A
Issue Date & City: September 22, 2018, Quechee, VT 05059
Art Director: Antonio Alcalá, Alexandria, VA
Designer: Antonio Alcalá, Alexandria, VA
Typographer: Antonio Alcalá, Alexandria, VA
Artist: Nadia Taylor, London
Modeler: Sandra Lane/Michelle Finn
Manufacturing Process: Offset
Printer: Banknote Corporation of America
Press Type: Alprinta 74
Stamps per Booklet: 20
Print Quantity: 400,000,000 stamps
Paper Type: Phosphor Tagged Paper, Block Tag
Adhesive Type: Pressure-sensitive
Processed at: Banknote Corporation of America, Browns Summit, NC
Stamp Orientation: Vertical
Image Area (w x h): .77 x 1.05 in./19.558 x 26.67 mm
Stamp Size (w x h): .91 x 1.19 in./23.114 x 30.226 mm
Full Booklet Size (w x h): 5.743 x 2.375 in./145.872 x 60.325 mm
Colors: Cool Gray 7, Cyan, Magenta, Yellow, Black
Plate Size: 800 stamps per revolution
Plate Numbers: “B” followed by five (5) single digits
Marginal Markings: Header: “Birds in Winter Chickadee, Cardinal, Blue Jay, & Woodpecker” 20 First-Class Forever Stamps • USPS logo • Barcode • Plate number in peel strip area • ©2017 USPS in peel strip area • Promotional text in peel strip area

Original announcement:
Birds in Winter celebrates four of winter’s winged beauties: the black-capped chickadee (Poecile atricapillus), the northern cardinal (Cardinalis cardinalis), the blue jay (Cyanocitta cristata), and the red-bellied woodpecker (Melanerpes carolinus).

Updated August 18th:
Here’s is the Digital Color Postmark for this issue:It measures 1.75″ x 1.37″. Here is the B&W pictorial postmark:It measures 2.87″ x 1.46″.