Are times correct in graph for historical actuals?

I’m trying to compare actuals for 24hr day last yr (may 23) to predictions in my TP, but in the graph I’m seeing most times are 4am to 4am with some times submitted as early as 3:30am-ish. I’m hoping the times in the graph are just off by a couple hours and 4am was really 6am. Can anyone confirm? Even if this is the case, did gates open early or are the actuals submitted before opening just people anxious to get in?