I have a specimen of this plant indoors that would have reached the ceiling several times over in the years I've had it - I just cut the tops off, usually in spring or summer, and let it regrow, so I can't imagine it would hurt your plant to cut it back where necessary. It might be better to wait till spring though, I think even Alicante has a sort of "winter" doesn't it!

Well it's mild up until about late January then we may get a cold snap. This plant isn't so much tall as wide! about 2 1/2 ft square.
Could I take out side shoots and move them elsewhere?

I've only just read your question properly! No, you can't divide the plant, but if you want more, do what I do - cut off all you don't want, then select some pieces and reduce them down to somewhere between 8 and 10 inches, strip off the bottom leaves, pop them in a bottle full of water, wait about 2 - 3 months and they'll be rooted, then plant where you want. I've just done a blog for Jacque on houseplants, and there is an example of what I mean in there - I did one earlier this year and its still in the bottle...

Thanks for that I'll have a look - bit worried now, I read a post from an Aussie gardener and apparently they can be quite invasive in the ground (at least in Austrailia) so possibly here too?

Can't help you with that one, Fenclare, being in Britain, only ever grown it in the house!