Graph-History save to file only till 23 h

If I save the graph history of a day it shows me the day vom 23 h (from the day before) till 23 h (of the saved day) and not from 0 till 24 h.
What’s wrong?

Also it will be very good, if the headline of the graph (with “weather diagram” CR “Current last 24 hours: ”) is not cutted resp. will be the same as in the automated generated day-graph-file(s).
Is this possible?