Any chance of a photograph of these plants?

Yes can you please give a photo Irene .

After a hellebore has flowered the petals (sepals) do not fall off but harden and the colour fades. These can remain on the plant for a long time though I would have thought a whole year a bit much. You will notice the seed heads forming in the center of these sepals at this time of year. We actually cut the old flowering stems off to the ground before the seed ripens so I don't see just how long they would remain.
Not sure what you mean by a different colour unless it is just the flower fadeing at the end of the flowering period.

Thanks very much I will try to get photographs uploaded
In answer to bulbaholic the first year they were white, then second pink and this year a very pretty maroon colour