I observe similar behaviour. I am GMT+2.
example: now it is 23:54 30th November 2018.
I have daily report for 29th with 9 kw and 30th is less than 1 kw for now. it is minutes before 1st December but it seems that in coldest day my split heatpump consumed 1 kw . :)
Of course 1st december usage will be logged on 30th november on top of that 1 kw .
Timezone is just wrong .