1. When you use terrain from the biofeedback preset it will automatically run its course for 11 days. You don’t have to do anything else manually. And yes, many people run it indefinitely. You can also run the all detox program.
2. For offline mode in GenX, there is no way to make the GenX move from one program to another. 8 of the 15 presets only run for 12 hours, this is why the total run time is 11 days, not 15 days.