No, this is based off the leaked source, just like UltraHLE 2064. But I question if there's a need for it any more with UltraHLE 2064 progressing so well. Maybe ShadowPrince should just contibute to UltraHLE 2046 from now on.
There have been a few small optimizations (one of them it better sound sync).
Shadowprince won't help uhle 2064. He released the 1.1.6 source-code when 2064 was released because he tought it was better. Knuckles removed it from the homepage but added it later again. Then the emu was on hold and Knuckles searched for new developers, and he found a few. Then Doggie released 1.1.7 unofficial but it broke more than it fixed. The emu was on hold again and there has never been a release again, but I hope it changes soon.
UltraHLE Alpha is still my best option for playing Zelda (unless 2064 has made big strides since I last checked -- do they have save states working yet?). It's faster than 1964, has smoother sound, and supports your choice of input plugins. And it has a decent GUI.