If you want to get a Mac code from f2s you need to chase up on the phone.

Its a pain due to the long holding times but its the only way in my experience. You need to call once to chase the leaving questionnaire thing and then again if you have not had the mac code within a few hours of sending that.

I got mine the same day I requested it - but only because I was determined to get it asap and rang up twice to hurry them along.