Perhaps I got lucky but I dropped to Silver for a few weeks in October during which time I had a family trip booked including one Y segment. I had pre-selected preferred seats and we manage to hang on to them.

I did have future travel booked which took me back to Gold a couple of weeks later, I did ring a few times in the days leading up to the flight trying unsuccessfully to upgrade and this was the only leg of four not in C - not sure if any of these points made a difference.