PlanetsCentral

I read somewhere that the "SSD" or imperial Assault ship does not grant planet immunity in P-Host somewhere, but I can't seem to find it now.

Anyhow, is that true in p-Host? If so what exactly is the point of the ship when they could just att or nuk the ship. Even if the planet/base would die fighting the Galleon or whatever it's called, it sounds like you can't exactly capture anything with it anymore if the opponent really doesn't want it too.