In no way am I trying to take away from something which seems to...

In no way am I trying to take away from something which seems to be to be a very positive announcement but I'm having trouble understanding the graph and need some help please. I'm assuming that the "Battery discharging" label points to where the red line lies beneath the blue line. I am also thinking that for the sections where the blue line is horizontal and equal to 5 the system is charging from the grid although only one segment is labelled as such.ie these are the charge part of the cycles. If my assumptions are correct, why then is there a red dogtooth hanging down at about 1.5 hrs into Day 2? This seems to suggest that the battery power is lowering despite the large amount of PV energy and the charging energy being injected into the battery. The PV energy alone (which can be estimated by the area under the curve) is quite large and probably exceeds the energy being lost (estimated as 5 units x 1.5 - presumably 25x1.5 kWH and so would become the main source of charging at this time. Any thoughts?