Don't count on being able to use the flights you've booked with GUC's prior to February 1st.
I had my flight repeatedly rescheduled across different routings. Eventually it found one with an impossible -10 connection. Foolishly I called customer service. The agent found another routing, which I told her clearly was acceptable only if the booking would be in Delta One. She changed it to a Main Cabin, and repeatedly insists that I authorized that. I've been waiting for a supervisor for 40 minutes, but even with a recorded line, I doubt this is getting fixed.