I think this is a similar case to that of Tsukuba Wet in GT4 and SSR5 wet in GT3 (Surprisingly, Gen III SSR5 has no dynamic weather).
Perhaps it's because SSR7 has no dynamic time (Or stars as I now realize)? If this was the case though, Gen III High Speed Ring, Eiger Road and Tsukuba Weather Change would be the same situation with reflections, and they're not. Hmmmmm....