The official first-day-of-issue dedication ceremony for the Harvey Milk Forever Stamp will take place at the White House on May 22 which is 'Harvey Milk Day' in California and would have been the slain civil rights leader's 84th birthday.
Writes the White House in its announcement:

Harvey Milk was a visionary leader who became one of the first openly gay elected officials in the U.S. when he won a seat on the San Francisco Board of Supervisors in 1977. Milk’s achievements gave hope and confidence to the Lesbian, Gay, Bisexual and Transgender (LGBT) community in the United States and elsewhere at a time when the community was encountering widespread hostility and discrimination. Milk believed that government should represent all citizens, ensuring equality and providing needed services.

His remarkable career was tragically cut short nearly a year after he took office, when he and San Francisco Mayor George Moscone were assassinated.

In 2009, he was posthumously awarded the Medal of Freedom by President Barack Obama.

The stamp image will be previewed at a later date and a public dedication ceremony will take place in San Francisco