In order to avoid time step restrictions where they are not necessary, a time step is only honored if the value at a certain time step is different from the value of the previous time step. In your example, the only steps that would have to be honored are days 366 and 380. From the screenshot that you have sent the time-steps curve looks OK to me. If you would like me to check the file in detail, please send it to support@dhi-wasy.de.