Justicar Syndra's spheres go dark after Lulu's Polymorph?

Hello, This afternoon I was playing as Syndra with her Justicar skin on against a Lulu in the mid lane. I was struck by Lulu's Polymorph spell, and once I turned back into the Dark Sovereign I noticed that the spheres orbiting her model reverted to her base skin (dark rather than light). Once I hit level 6 and used my ultimate, the light spheres returned and layered over the dark spheres creating some really awesome looking light purple spheres. Is this an in-game interaction feature? I was wondering if it might be a bug. Hope this helps! Thanks,

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