Hmm, I thought it would error at the end of installing like a normal pkg update over an fpkg. If it's an official, base game, then I could see that happening. You could disable the Internet. Other than that, I'm not sure. You can block Sony with most routers or a proxy though, which is what I used to do. My router at the time couldn't block URLs, so I used ccproxy. Only problem is that your computer must be on and ccproxy open to use the Internet on the PS4.