Royal Worcester mark to identify age and artist if possible

Hi,
Can anyone tell me what year this mark represents. I have looked but become quite confused because of the dots at the top…they do not seem to correlate to the represent years. i would love some help please? its a Royal Worcester hand painted Daffodil pedestal bowl.
Very rare it seems as there is no other on eBay. I wonder who the artist was?
Thanks. Xx