My understanding of the ZRH situation is that it is doing very well in J and PY, average in F and really poorly in Y.
Now, this is a challenge with the 77H, but even worse with the 359 which has 214 seats in Y, as compared to 182 on the 77H. So the 359 is no solution for the ZRH demand mix.
This mix is typical for ZRH, other airlines such as SQ experience the same, so airlines usually deploy J heavy aircraft to ZRH, if they have any.