Zanussi selector knob stuck?

I have a Zanussi washing machine model FJ 1295 with a pop-out selector knob. The knob is stuck in the closed position. How do I release it? I have got as far as removing the top cover to the machine and releasing the 5 clips which appear to hold the front fascia but the fascia is still firmly held by something else. On the underside of the fascia there appear to be three small slots where I might introduce a screwdriver blade to release further clips - am I on the right track? Many thanks.