It appears to be a Pentas lanceolata of some variety - not hardy during the winter, so if you want to overwinter it and put it outdoors next year, keep it somewhere bright, away from draughts but also away from heat sources. Harden off and move back outdoors when air temperatures are 18 deg C or above.

Thank you. Would it be Ok to overwinter it in a potting shed?

No, it needs continuing light and water, like most tropical plants. I would keep it as a houseplant, a little back from a south or west facing window.

It is a tropical plant, and never goes dormant enough to be stuffed in a corner. I would keep it as a houseplant, a little back from a sunny window.

Thanks very much. So maybe it will do OK in the conservatory, which is heated in the daytime, but not overnight?

Depends how cold the winter is and how cold your conservatory gets overnight really, but I've found a link which suggests it is possible to simply overwinter them indoors and then replant outside. The method resembles that used for Fuchsia, where you dig them up, cut back and pot them, then keep them somewhere frost free, giving water occasionally, then increase watering in very early spring, maybe potting on as well, and starting it back into full growth ready for placing or planting outside again when temperatures are high enough. Link below, the bit you're interested in is under Use and Management, towards the end. If you read it all, its obviously American, but it might be useful to know that most of the UK is Zone 8

https://edis.ifas.ufl.edu/fp465

Thank you so much!

Oops! I was having conection problems that night, and I thought that I had lost my first post!
I'm glad that you found that site, Bamboo. That is the first time that I have heard that it is possible to do that with Pentas. Learn something new every day!

Yes, Tug - I've concluded one of the reasons I like Questions on garden websites is it gives me a reason to do research - and I learn a lot more too! Course, whether I remember what I've learned is not guaranteed...

My father always said, "I have a photographic memory, but I ran out of film."

Ooh, that's a good one, Tug, better than my usual 'must have lost more neurons so the info is having take the long way round to get to my mouth'. Which could be up to a week in my experience, very annoying having an answer arrive 5 days later when you're on the verge of sleep! Although that is literally what's physically happening, most people have no idea what I mean...but they still laugh, and then I have to explain...