

Assuming you can change the future, you can send a message with your location history every x minutes to your 1-day (or more) ago self. You will have to encode it (and I guess this should be done outside the phone) in a way that the assassin can’t spoof a message. You’ll have to figure out that encoding as soon as you find out about the assassin since that’s your message travel limit anyway. When you start receiving messages you follow that location history and then stop following it when you stop receiving them because something went wrong there. Eventually some instance of you might make it 7 days.
Wish it worked like that with the lights. I don’t like artificial light so only have some back lights on or none at all most of the time. And will sleep until 1pm with two big windows without blinds in my room.