there is no dormant period as such for these so repot at any time of the year
I didn't know that was the case, pardon my mistake.
well.. to be fully accurate.. Dormancy in (sub) tropicals is not the same as dormancy in our outdoor friends. They DO go dormant. Look at ficus, who will slumber for weeks, months on end, and all of the sudden jump in a growing spurt.
I am not sure however when the best time for repotting tropical is. I have done both when dormant as when actively throwing new leaves out. Have not really seend a difference and therefor do it when it suits me.
Once the plant is really growing, so showing good extension on several branches, loko at cleaning up the mess. There are bulges on the branches. dead stumps, multiple branches in a single point (I think). Just make sure the plant that you are growing, ill actually have a future as bonsai, or else all work is for naught.