The POTA program has been in the process of changing all park prefixes from their original format to a new format that follows the ISO standard for naming entities. On March 20, 2024, parks in the US will change from being listed as “K-xxxxx” to “US-xxxxx” (the K changes to US).
Changes for other countries have either already taken place or will take place soon. For example, The Bahamas used to begin with C6, and is now BS.
Keep in mind that there never has been a requirement to transmit your park information, not even if you are doing a park-to-park contact. All of that is automatically handled when logs are uploaded. But you will certainly see these changes on the POTA spotting network, and will likely hear them on the air soon. Just remember to send “US” starting March 20th!!!
See this URL for information: https://docs.