My pump backup plan was the thing I never wanted to need

I have been thinking about what someone should keep in a written backup plan in case their insulin pump suddenly stops working.

A pump failure can happen at inconvenient times, and it seems important to know what steps to take instead of trying to figure everything out during a stressful situation.

For people who use pumps, what information have you included in your backup plan? Did you write down your insulin details, emergency contacts, supplies, or steps for switching temporarily to another method?

I'm interested in learning what experienced pump users keep ready for unexpected situations.