Q.I Have An Unusual Calla Lily.
I’ve raised numerous colors of Calla Lily’s for several years. This year one of the first blooms is something I’m not familiar with. Is the attached Lily normal. Sure is nice. The first color showed on a leaf and then the blossom developed beneath the leaf.

Certified GKH Gardening Expert
This is not the first, this year, that I have seen this! I'm not sure what is causing it, but mutations can happen for many reasons.
https://www.gardeningknowhow.com/garden-how-to/info/what-is-plant-mutation.htm
https://www.gardeningknowhow.com/garden-how-to/info/plant-sport-mutations.htm