The widget labels the days with a letter, but I’m assuming it’s days from a different time zone.
All the activities shown here appear on the day prior to them actually happening.
I‘m in New Zealand, ran 18km this morning (Saturday) and the graph is showing it as F(riday)
The other noticeable item for me was a bike rule i did on Wednesday, which shows up here on Tuesday
Interestingly, now that most of the rest of the world is also in Saturday, that same graph has updated: