Just found this blooming.
This is a mericlone called Den Enobi Purple 'Splash'. Don't know too much of background of plant. Flower variegation probably originated as a sport from the hybrid cross. This kind of flower variegation (chimera) does not usually come through in mericlones except in very low percentages. Usually clone flowers would be either all purple or all white, with very few with the variegations.