I had a similar incident 2 years back. I was booked on an award ticket (U) from London to Florida. They cancelled flights to Florida for 4 days in a row due to weather issues (hurricanes). My original flight had no U availability for 8 days. They were more than happy to rebook me any day to any destination that U was available. I got to fly to an alternative Florida destination 4 days later...
Now I now better....