This issue was finally announced by the USPS on March 20th. No date of issue was given. The first landing on the moon occurred on July 20, 1969.
[press release]
U.S. Postal Service Unveils
1969: First Moon Landing Forever Stamps 
WASHINGTON — In celebration of the 50th anniversary of the first moon landing on July 20, 1969, the U.S. Postal Service is pleased to reveal two stamp designs commemorating that historic milestone. Additional details are coming about the date, time and location for the first-day-of issue ceremony.
One stamp features a photograph of Apollo 11 astronaut Buzz Aldrin in his spacesuit on the surface of the moon. The image was taken by astronaut Neil Armstrong. The other stamp, a photograph of the moon taken in 2010 by Gregory H. Revera of Huntsville, AL, shows the landing site of the lunar module in the Sea of Tranquility. The site is indicated on the stamp by a dot. The selvage includes an image of the lunar module.
Art director Antonio Alcalá designed the stamp art.
Further updates will appear below.
Updated March 29th:
These stamps will be issued Friday, July 19th in Cape Canaveral, FL.
Updated June 1st:
[press release]
U.S. Postal Service Issuing 1969: First Moon Landing Forever Stamps
What: The U.S. Postal Service is celebrating the 50th anniversary of Apollo 11 and man’s first steps on the Moon with two Forever stamps.
The stamp dedication ceremony is free and open to the public. News of the stamp is being shared with the hashtags #MoonLandingStamps or #AstronautStamps.
Who: Thomas J. Marshall, General Counsel and Executive Vice President, United States Postal Service and Dedicating Official
Steven W. Monteith, Vice President, Marketing, United States Postal Service
Col. Robert D. Cabana, Director, John F. Kennedy Space Center, NASA
Russell L. (Rusty) Schweickart, former NASA astronaut and scientist, NASA
When: Friday, July 19, 2019, at 11 a.m. EDT
Where: Kennedy Space Center Visitor Complex
Space Commerce Way
Merritt Island, FL
RSVP: Dedication ceremony attendees are required to RSVP at usps.com/moonlanding.
Background:
On July 20, 1969, Apollo 11 astronauts Neil Armstrong and Buzz Aldrin achieved something that had long been confined to the realm of science fiction when they landed a spidery spacecraft named Eagle on the Moon. A worldwide audience watched and listened when Armstrong stepped onto the Moon’s surface and famously said, “That’s one small step for (a) man, one giant leap for mankind.”
On the 50th anniversary of this first Moon landing, two stamp designs commemorate that historic milestone. One stamp features Armstrong’s iconic photograph of Aldrin in his spacesuit on the surface of the Moon. The other stamp, a photograph of the moon taken in 2010 by Gregory H. Revera from his home in Madison, AL, shows the landing site of the lunar module, Eagle, in the Sea of Tranquility. The site is indicated on the stamp by a dot. Art director Antonio Alcalá designed the stamps.
The 1969: First Moon Landing stamps are being issued as Forever stamps. Forever stamps will always be equal in value to the current First-Class Mail 1-ounce price.
From the June 6th Postal Bulletin:
On July 19, 2019, in Cape Canaveral, FL, the United States Postal Service® will issue the 1969: First Moon Landing stamps (Forever® priced at the First-Class Mail® rate) in two designs, in a pressure-sensitive adhesive pane of 24 stamps (Item 479100). The stamps will go on sale nationwide July 19, 2019, and must not be sold or canceled before the first-day-of-issue. The 1969: First Moon Landing pane of 24 stamps may not be split and the stamps may not be sold individually.
On the 50th anniversary of the first moon landing on July 20, 1969, the Postal Service™ is pleased to issue two stamps commemorating that milestone in history. One stamp features a photograph of Apollo 11 astronaut Buzz Aldrin in his spacesuit on the surface of the moon taken by astronaut Neil Armstrong. The other stamp, a photograph of the moon taken in 2010 by Gregory H. Revera from his home in Madison, AL, shows the landing site of the lunar module in the Sea of Tranquility. The site is indicated on the stamp by a dot. Art director Antonio Alcalá designed the stamp art.
Availability to Post Offices: Item 479100, 1969: First Moon Landing (Forever Priced at the First-Class Mail Rate) Commemorative Pane of 24 Stamps: Stamp Fulfillment Services will make an automatic push distribution to Post Offices of a quantity to cover approximately 30 days of sales.
Special Dedication Postmarks must use this design:
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 – 1969: First Moon Landing 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 November 19, 2019.
Technical Specifications:
Issue: 1969: First Moon Landing Stamps
Item Number: 479100
Denomination & Type of Issue: First-Class Mail Forever
Format: Pane of 24 (2 designs)
Series: N/A
Issue Date & City: July 19, 2019, Cape Canaveral, FL 32920
Art Director: Antonio Alcalá, Alexandria, VA
Designer: Antonio Alcalá, Alexandria, VA
Typographer: Antonio Alcalá, Alexandria, VA
Existing Photo: NASA photo taken by Neil Armstrong
Existing Photo: Gregory H. Revera
Modeler: Sandra Lane/Michelle Finn
Manufacturing Process: Offset
Printer: Banknote Corporation of America
Press Type: Alprinta 74
Stamps per Pane: 24
Print Quantity: 60,000,000 stamps
Paper Type: Phosphor Tagged Overall
Adhesive Type: Pressure-sensitive
Processed at: Banknote Corporation of America
Colors: Cyan, Magenta, Yellow, Black
Stamp Orientation: Vertical
Image Area (w x h): 0.84 x 1.42 in./21.336 x 36.068 mm
Overall Size (w x h): 0.98 x 1.56 in./24.892 x 39.624 mm
Full Pane Size (w x h): 7.6 x 8.5 in./193.04 x 215.9 mm
Press Sheets Size (w x h): 22.8 x 25.5 in./579.12 x 647.7 mm
Plate Size: 216 stamps per revolution
Plate Numbers: “B” followed by four (4) single digits
Marginal Markings:
Front: Header: 1969: First Moon Landing
• Plate number in bottom two corners of pane
Back: ©2019 USPS • USPS logo • 2 barcodes (479100) • Plate position diagram • Promotional text
Here are the first-day postmarks for this issue:
The Digital Color Postmark measures 2.97″x1.45″ 
The B&W pictorial measures 2.98″x1.36″ The special postmark for use by local post offices measures 2.64″x0.88″
Updated June 22nd:
Canada is issuing its own Moon Landing anniversary stamps on June 27th, commemorating Canada’s contribution to the effort. The designs will not be released until the first-day. What we know is here.
OTTAWA, Jan. 4, 2019 /CNW/ – Postage rates rise on January 14, with the price for stamps purchased in a booklet, coil or pane for domestic LettermailTM items weighing 30 grams or less increasing to $0.90, up from $0.85. The price of a single domestic stamp will increase to $1.05, up from $1.00.
A third stamp portrays the famous golden spike that was a prominent part of the ceremony. Each of the stamps and the header feature gold-foiled highlights that produce a glimmering effect. Art director Greg Breeding designed the issuance. Michael J. Deas painted the Jupiter and No. 119 stamps. Kevin Cantrell illustrated the stamp depicting the ceremonial golden spike and did the border treatments and typography for all three stamps.
Issue: Transcontinental Railroad Stamps
Image Area (w x h): 1.7828 x 1.1592 in./45.283 x 29.444 mm
The Digital Color Postmark measures 3.00″ x 0.86″ 
The B&W pictorial measures 3.00″ x 1.5″
