While I agree free dining is a great offer - especially in the values or for larger families - I don't think it will sell out overnight. We went during free dining last year, and did not book until mid-June. In fact, the original offer was extended (from April to June?) - most people have surmised this is because there were not enough bookings by the original deadline.
I do believe it will sell out sooner, especially with advance sales via the UK and bounce-back offers. A more limited inventory of dates will have an effect, too. However, as sweet a deal it is, there are still a number of people who simply cannot afford annual trips to Disney, even with free dining. Some of us will not switch to free dining as the 40% offer will be a better deal.
By all means, don't delay if/when it is announced, and keep an open mind re: resorts you'll book. However, I wouldn't stress too much before any announcement.
I do believe it will sell out sooner, especially with advance sales via the UK and bounce-back offers. A more limited inventory of dates will have an effect, too. However, as sweet a deal it is, there are still a number of people who simply cannot afford annual trips to Disney, even with free dining. Some of us will not switch to free dining as the 40% offer will be a better deal.
By all means, don't delay if/when it is announced, and keep an open mind re: resorts you'll book. However, I wouldn't stress too much before any announcement.