Hi John,
Generally speaking, it is possible to begin making Advance Dining Reservations at 180 days out for Table-Service restaurants at the Walt Disney World Resort, either online or by calling (407) 939-1947.
However, as far as Paddlefish is concerned, this restaurant has yet to be added to the Walt Disney World website and to my knowledge, no official opening date has been announced for this particular restaurant at this moment in time.
The most up to date, official, information that I have seen regarding this dining location was posted on the Disney Parks Blog back in May in a post titled "
Paddlefish Opens in Fall 2016 at Disney Springs."
My best advice to you would be to subscribe to the Disney Parks Blog as this is the place where any details regarding an opening date and the date that it will be possible to start making Advance Dining Reservations for this dining location will most likely be announced.
Wishing you a magical trip filled with memories which will last a lifetime!
Emma