I've never particularly known how/when to prune stuff, and my bottle
brush was no exception, it had got a bit straggly. This year if
flowered very well and I took the time to read-up on pruning, and the
advice seemed to be prune immediately after flowering, right behind the
flowers.

The plant seemed to react well to this, I gave it some feed and kept
watering it, it bushed out nicely from the points where it had been
pruned, because it had "filled-out" I also lopped off some of the dead
twigs.

Looking out the window just now, I noticed one small section is back in
flower, and lots of the new growth seems to have buds ready to do the
same, wonder if that will confuse it when the weather turns, or mean it
doesn't flower very well next year?