Not realistic, provided EECs are working the Np should never go below 70.8% on ground with condition levers in AUTO, which should engage the ACW generators above 63%. Doesn’t matter what the conditions are, that is how the real aircraft works.
@Puttishuu82 to you as well, that is clearly a bug.
There is one edge case where, after landing, if you select reverse before LO PITCH is illuminated, the Np can drop momentarily and causes a short loss of ACW. But this is only transitory.