I think I quoted the LCY CEO earlier in this thread that performance-wise, the A318 should do nicely but that it will be a major headache on the apron at its current size.
Similar problem with the DH8-Q400 which is longer than the largest BAe 146 with a
wing span of 28.42m (93ft 3in) and a length of 32.84m (107ft 9in).
With the Avro RJ no longer produced, there clearly is a need for a 100 seat jet aircraft that can serve LCY once the Avro RJ are due for retirement.