28 Hours Later
There is a script called 28 Hours Later, completed and visible online.
I know this is true, I wrote it myself! ππ
The story is a prequel to "28 Days Later" as well as a follow-up to its first scene, inside the lab. It shows what happens as the virus breaks out, when '28 Days' jumps four weeks. And it's supposed to end 28 hours after the outbreak, as the Royal Family is evacuated.
Enjoy, don't hesitate to share your thoughts!
http://www.simplyscripts.com/scripts/28HOURSLATER.pdf
DNA Films, the London production company that owns the rights of the franchise, already knows about this script. I submitted it to them in 2015, unsuccessfully - they didn't even have an eye on it.