I am no rose expert but I am led to believe roses are sometimes grafted. Maybe you have a sucker from the stock rose.

Thanks. I did read about this but I guess we all really wish to have a wonderful new variety, lol.

It is very pretty. I'd keep it like this. Have you seen the pretty patio standard roses with two colours, lemon and pink, which are very different?

Well you might have a sport - neither of these different roses look anything like sucker growth - the growth off rootstock is always long, often straight and thorny and produces dog rose type flowers, usually pale pink, open and flat, nothing like either of the flowers you have there.

There may have been some genetic reversion back to one of the original parent crosses in part of the growth, or genetic alteration/mutation producing that rather lovely peachy coloured rose.

Cammomile - I will look up the patio standards you mention.

Bamboo - OOOh! Curiouser and curiouser. How can I be absolutely sure? I am guessing taking it fairly rapidly to a rose expert locally would not go amiss.

The pink/peach rose is far more attractive and long lasting than the yellow and that makes me wonder why they would use such a beautiful rose simply as root stock.

If you know a rose expert, then ask them, otherwise try the RHS, they might have an answer...

Beales roses at Attleborough [Norfolk]are very helpful. send them the picture and they may be able to id the original and the other part.

Thank you for all of your advice it is much appreciated.

I have written to Beales roses and also David Austin roses for advice on it.
I will update with any findings.

Thanks again.

Update 1 -
I have had a reply from one specialist grower who said "Wow" to start their reply.
They said "it certainly looks like a sport" and "If you are interested, for a fee we could try to propagate this rose for you and perhaps it will stabilise as a new variety! This is certainly a very slim chance and often these one-off sports are short-lived and unstable so not seen for longer than a season or two". Followed by "the charge will be for using the stocks as they are very limited and the staff time to graft and monitor this for you"

As they are too far from me to travel to I suppose this would be out of the question anyway but what are your views, should I if possible or not? Is it worth a shot?

my first thought is how much will it cost you and how much will they make out of you?

I think i'd wait and see if it does the same thing from the same stem next year. If it does then you can always look into it in more detail.

Well said, I will do exactly that. No rush and see what transpires next season. The spur is growing well with lots of fresh growth from it and it is healthy.

It is pretty windy here today and I have just noticed on the newer yellow rose stems a couple of the petals have pink/peach stipes down them. Not overtly obvious at first but the wind allowed me to see them. I will post an image asap.

Could not see how to add images to this post and so added them to original.