I am not so sure that is the reason - LUX use the Q400 at LCY.....it is more a Flybe decision rather than a/c restraints. I doubt Flybe would use the E195 to LGW as there is not sufficient demand on the route - that is to say not consistently high anyways. They could possibly use the E195 on the busier IOM-LGW service on a W Pattern through LGW but I doubt this will materialise.