You know that you'll be coming back to the present, but don't know exactly when. It could be a day, or it could be a week, but no more. Your electricity, plumbing, and your router works, and somehow you have internet access. You are geographically where you are now, so you could be miles from civilization, or in the heart of the city. Nothing is destroyed for you to exist, so if you're in a building that is on the site of something that was torn down after 1950, you're somehow above it. You need to be careful of accidentally starting a pandemic, so you want to try to limit your exposure to people, just in case you have a modern infectious disease and don't know it.