It doesnt have more than one digital reading display..it is the same display but there are 2 dotted arrow lines lines below it instead of one. A top line will have the dots moving to the right...delivering..the bottom line (when solar is on) will have dots moving to the left..receiving. (by Edison).
So, I guess that means we don't know what happens after it goes backwards and "zeros out" (it actually diplayed all 999999). Maybe someone else would know? Thanks for replying though...truly appreciated.