I have used a large number of ADP3331 (+10) in a precision instrument circuit to generate voltages of 1.8, 3.3 and 5 volts.
In this circuit, I have used the values of the resistors in Table 1 (page 7 of the datasheet). But the feedback voltage is 0.75-0.85V instead of 1.204V, while all output voltages are exactly the desired values.
The question is whether it is necessary to have a voltage of 1.204V on the feedback pin or whether it is sufficient to stabilize the output voltage with any amount of voltage on the feedback pin.
It should be noted that the operation of the circuit is completely consistent with the datasheet.