My backup battery input is tied directly to the main battery and has never failed when shutting off the master, so it isn't too likely an issue, but...
In the AFS v16 software from December 2020, AFS doesn't have a drop down entry in the oil pressure and fuel pressure configuration pages specifically...
I have installed the high burst pressure replacement Kavlico sensors and according to the above post they are directly selectable as fuel and oil PSI...