I'm watching through Dallas, and I'm to season 9 (by the DVD numbering; I understand it was previously called season 8). Patrick Duffy left at the end of season 8. Season 9 is all a dream Pam was having one night, leading up to the infamous shower-reveal. What I'm wondering is, at what point in the process was it decided that season 9 would be a dream? Was this a last-minute thing? Or did the writers know it was coming at some point earlier in the season?
Essentially, how much of season 9 is written to be "reality" and how much is written to be Pam's dream?