Korea Post will issue two stamps on 12 August, 2022 in what appears to be a new series called ‘Foreign Advocates of Korean Independence’. The date of issue is close to ‘Liberation Day’ (해방의 날, Haebang-ŭi nal), 15 August, the date in 1945 when Japan surrendered, thus both ending the Second World War and her occupation of Korea. The two issues commemorate the lives and work of the American missionary and educator Homer Bezaleel Hulbert, and the British journalist Ernest Thomas Bethell who both were involved in the advocacy of Korean independence at the beginning of Japanese colonial control.
Following the Meiji Restoration (1868) when Japan began its rise as a world industrial power and the assertion of her geo-political dominance in East Asia, dominance in Korea was a key part of Japanese plans. Defeat of China in the First Sino-Japanese War of 1894-1896, and the subsequent defeat of Russia in the Russo-Japanese War of 1904-1905 made Japan the pre-eminent power in East Asia. Britain entered into an alliance with Japan at this time as a counterbalance to Russian power in Central and Northeast Asia. Korea, as a weak state, became a pawn caught between the Great Powers. Ironically, many foreign residents in Korea during this period had a favourable view of Japan because it had successfully modernised. This view changed from the middle of the 1890s. Hulbert and Bethell were two foreigners who worked, in different ways, to support Korean independence.
KoreaPost has released the new issue leaflet. This gives all sorts of details for these stamps, such as size of the stamps, numbers issued, etc.
KoreaPost has now released images for both the FDCs and the Maximum Cards for this issue.
Here are the FDCs (front and reverse):

And the Maximum Cards:
