Sold at a premium to benefit Ukrainian refugees (a "semi-postal"), at the "Forever" rate and plus, the design is a one-last-issue revival of the Overrun Countries series of World War II.
The original series sold at a 66-percent premium (5 cents instead of 3 cents) as "V-mail" for correspondence...
Credit to the YouTube channel "Today I Found Out" for bringing this to my attention for the first time:
Yang Kyoungjong - Wikipedia
Basically, this Korean guy was living in Manchuria when he was drafted by the Japanese to fight against the Soviets. He was captured by the Soviets and sent to...