Choisya pruning advice please: urgent?

Choisyas are determined to grow so have a go ....I would do it now?
Also check for branches that may have layered themselves; if so sever them and pot up or plant out.

 

Sorry, I`ve been slacking Martin. I actually grow a lot of Choisya, and it is among my favourite shrubs. C. ternata, and C. aztec pearl are really tough, and I`ve pruned both of these within an inch of their lives - in fact a couple of years ago one of the 'aztec pearl' shrubs was knocked back to about 2 inches by accident, and it is now flourishing once again.
I tend to prune now rather than springtime, as the birds are looking for nesting places then.
If you decide to grow 'sundance' the yellow leafed variety, it is happier with some shade away from windy spots.

 

Yes @Verdun the 1 I dug up had 5 layers. I replanted all of them and 4 took. I am probably going to have another sale for charity in the Spring so might pot these up and sell them.
Choisya can struggle up here in Scotland and needs to be in a fairly sheltered spot to do well I've found.....suppose we don't have the same climate as Mexico! For this reason I always tend to prune mine in the Spring to give the new growth time to toughen up during the Spring/summer. Down in your and Tetter's neck of the woods you won't have this problem. Not sure where Martin lives so thought maybe better to be safe than sorry but agree in warmer parts it would be fine to prune now.

 

Choisya is one of my favourite shrubs. I would prune it back now ( early autumn ) . They are really tough , so you can cut it back hard . Remove any damaged branches and crossing growth until it is the size / shape you want .