what clematis??

we have this clematis but what variety
1st flush in april/may
2nd flush july/august
and now a third flush
1st flush produced only 2 flower heads about 10" across
but subsequent flushes only 5 or 6" across ??

regards and thanks for any suggestions

 

Do you have a photo of the inside of the flower?

That would help!

 

I'll get one when the first flower head is fully developed.
probably tomorrowish.

regards

 

here is the flower head fully opened