Booking period is over. It is slightly possible it will be reopend but if that happens I would not expect it until Oct. for Nov/Dec trips. Disney will see how bookings go the next month or two.
I have a different situation. I have a trip booked and paid for but may want to add another persion. I am not sure if Disney will allow me to add 1 more person to our trip and have them get the
free dining. Our ADR's will have to be adjusted but some are already for 1 more person than we have as plans have changed up and down the past few months.
In past years Disney has allowed people to be added and get free dining past the booking period as long as total allotmant for free dining has not been exceeded for the days of our stays. Have to call later to see what current policy is.