LTM8046 input voltage range vs output voltage


I want to convert 28V input to 5V,450mA isolated output by using LTM8046 . In datasheet, says LTM8046 maximum input is 31V .  However, DC1559A demo board specifies input range maximum 26V, also in datasheet circuits.

Is the input maximum voltage depends the output voltage?

Is 31V input only for the output below 3.3V?