That's correct, Zurich won't be back. With the B737-300s and B737-500s going they don't have the correct capacity for some routes anymore. The series 400 is a little large as is the A319. Gatwick is coming full circle to be a leisure oriented BA base, with most of the Club heavy routes at Heathrow.
British Airtours anyone? I think easyJet have been very succesful in building up Gatwick but the South Terminal is, lets be honest crap. I bet they'd want the whole operation from the North Terminal but with BA still in situ for a few more years, I don't think the capacity is there alas.