In the Winter, A3 operates the morning rotation to LHR only on 1----67. This goes back to the OA era. Complementary to these morning flights, it operates to LGW on -2345--. However, as I see it now, this flight to LGW will operate only for December/January (just in time for x-mas), so there is a reduction indeed.
They will announce new routes for S18 soon though