(1) Simulation time entry field is in seconds. If you set simulation time less than 10hours(36000s) say 5000s then simulation stops at 5000s. Only the data till 5000s would have been used by the simulaton.
(2) By default, matlab interpolates data inbetween. Time step is defined by the solver. If you use fixed step solver, then you have the option to define your time step in Model Configuration.