You would have to grow out several generations to see if there is something consistant and noteworthy about it before calling it a sport. Even though you're growing them side by side, I often see that amount of variation between offsets from the same mother. It's not just light levels. Pot size, fertilizer, and any number of other variables can have an effect, and sometimes there is no obvious explanation.

I don't believe in naming every little variation anyway. Cultivar names should be reserved for something that is significantly different, stable and desirable.

Thanks Lisa for your well reasoned comments. We certainly don't want to be bogged down with yet another recurvata cultivar for the sake of it. I guess my main question was, is this within the normal variation of this species. I've had this plant in my possesion for about 30 years and it's always been the same. But to see it change suddenly made me question what's happening.

Cheers

Brod