Please see below diagram from the MTZ Neutral Current Transformer Instruction Sheet
.As you can see, H1 is always oriented to the bottom side (of the breaker) and H2 to the top side (of the breaker).
In fact, the CT is always installed in the same way whatever the way the breaker is fed (top or bottom).
Please see the below illustrations for better understanding.
You can install the neutral CT above or below or same level as the breaker, but H1 side of the neutral CT is always facing the direction where the bottom of the breaker is. Please see below.
The reason for this is that the internal CTs installed inside the beakers, face their H1 side towards the bottom terminals of the breaker. Since, we cannot change the orientation of the internal phase CTs, we have to match the same orientation in the neutral CT as well. i.e. H1 is always oriented to the bottom side (of the breaker) and H2 to the top side (of the breaker)