Looks like you found a new luminescent ink variety if it matches the LW UV image below. The colors at he top of the stamps look off because the shiny surface of the stamps causes a lot of glare. I was not aware of it. In this case the yellow ink is causing the effect. Nice find!
As an FYI, I started at the 5 cent issues and I have been working my way through every issue and have gotten up through 1998 looking for luminescent ink varieties. Hadn't gotten to 2003 yet. Right now the list of regular US issues starting with Scott 1036 that have luminescent & non-luminescent varieties stands at over 100. I will publish once I get through the stock I have.