As far as a Silver Phoenix, the color is more of a Silver Duckwing than a color of their own. Just like the Silver Duckwing, the hens have the brown chest, white and black hackles, grey back, wings, and saddle, and a black tail. On the rooster, they have the black chest, wingbar, and tail with the white hackles and saddle, just like the standard Silver Duckwing color. (In fact, I believe I've heard some people refer to the Silver Phoenix as a Silver Duckwing Phoenix.) As far as the tail, I have had some young EE mixes who did have a much longer tail. Your pullet might just have a longer tail and may grow into it as she grows.
One of my current EEs:
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