I don't ever want to rush the chap but a lot of the work in terms of useable assets etc for ROTJ:R are already in Ady's hands.
The Blu-Rays are out so no waiting around to see if there are useable deleted scenes.
Items like the carbonite block will be made by the time ESB:R will be finished and wont need to be rebuilt.
The camera and many of the models used on this project can be used for the next one.
Guys like Ming have already been found, tested and are pretty much certain to be up for some more fun.
It will take time (Ady is a perfectionist) but some of the delays this time may make the next project come faster than if they hadn't happened.
In building this project I'm sure he has developed previously learned skills and picked up some new techniques which will make what he wants to do easier.
Unexpected delays like the sad an unpredictable family upsets in Ady's recent past you can't plan around.
But I'm sure that all the ideas for ROTJ he already had and some of the input of other people on the conceptual threads here will have have made his job easier next time.
Some of the other ROTJ edits have either proved some things possible and attractive to him or helped him decide which ideas are unworkable or undesirable to him too.
Ady thought that this would be the relatively easy film to do and ROTJ would be the big challenge but this is a well loved film already so in someways it's the easiest to screw up.
Jedi and the PT offer Ady a bit more creative freedom.