Best time for pruning these is spring - if its essential to remove a little here and there because its in the way, then you'll have to chance it. Link below gives more guidance

https://www.rhs.org.uk/advice/profile?PID=168

Hi welcome to GoY, it depends where you are in the world, if you're in the southern hemisphere then it's probably flowering round about now, and you can prune when it finishes flowering, in the northern hemisphere, if you prune now, you wont get any flowers next year, this is pruning group 8, just removing any dead, diseased or crossing branches, and any that spoil the symmetry of the plant, after flowering, Derek.

Sorry Bamboo, there was nothing there when I started typing, Derek.

Not a problem Derek...