Are you using the latest version of this component?
I have retested this here with a default TPlanner on the form and initialized with:
begin
planner1.Display.DisplayEnd := 54;
with planner1.CreateItem do
begin
itemstarttime := encodetime(19,0,0,0) + encodedate(2013,2,11);
itemendtime := encodetime(02,0,0,0) + encodedate(2013,2,12);
end;
end;
and this correctly shows the item from 19h , crossing 0h00 and ending at 02h00.
It is also correctly ending at 0h00 when I use the code:
begin
planner1.Display.DisplayEnd := 54;
with planner1.CreateItem do
begin
itemstarttime := encodetime(19,0,0,0) + encodedate(2013,2,11);
itemendtime := encodetime(02,0,0,0) + encodedate(2013,2,12);
end;
end;
What is different in your project?