Forgive the "Re-Post", but... You want a plan in place... NOT ONLY FOR YOUR DEATH! But for any situation which leaves you unable to care for your tank(s).
Last year I was perfectly healthy on a late January Friday, Sick with the FLU on Saturday, Admitted to the Hospital on Sunday and in a coma by Monday evening. It all happened so fast, I, nor anybody thought about my eight freshwater fish tanks.
Long story short, I was in a coma for three weeks and couldn't communicate for another week. By the time I was able to communicate, four of my tanks had crashed. By the time I got home, I had lost well over 100 fish, and six tanks. Within the next month, I lost all but one fish.
I shut down my fishroom, cleaned tanks, admittedly shed a few tears and seriously thought about hanging up the aquarist hobby. My wife, however, encouraged me to pick it back up because I do enjoy it. However, this time as I build, I am making water changes and regular maintenance SUPER easy and ALL CARE instructions will be shared with my wife and someone locally who also has tanks with an agreement to help each other out in such an event. I am in the re-building process now, but I will not add one live creature to my tanks until such an agreement is in place.
I learned the hard way.... If you are reading this, You don't have to.
Join a local club. Get to know other Aquarists in your area. Exchange phone numbers and ensure that you post their phone number in your sump area, or somewhere it can be easily found and inform your friends and family they are to call that person should you not be able to. You may save yourself thousands of dollars!