Live photos CAN exceed 3 seconds...But can you convert them to videos longer than 3s?

I hope to better understand Live photo length. Apple (and all other online discussions I have been able to find) state that Live photos have a limit of 3 seconds. I take Live photos on my iPhone 6s all the time that exceed 3 seconds. And to be clear, I am very tech savvy and am not mistaking videos for Live photos. And I have not edited any of my live photos with 3rd party software, nor have I saved other photos from external sources. The photos in question are all taken using the camera app on my iPhone 6s, running iOS 14.7.1

My biggest question is, how can I convert a 6 second Live photo into to a video that is not cropped down to 3 seconds? I know how to "Save Live photo as video," but the results always end up 3 seconds long, regardless of the length of the Live photo.