Copeland Spode Bird Plates, cups & saucers

I'm trying to identify this Copeland Spode Pattern
It's a beautiful set of 12 plates, cups & saucers, each has a different bird in the center. On the back is Spode Copeland, Anthony Chaplin and on the plates are the marks Y5860, Y5861, Y5863, Y5857, Y5862, Y5858, Y5860

On the cups and saucers there are also Y marks with the numbers 6043, 6039, 6044, 6041,6040

any help with age, pattern name or really just any info would be much appreciated

I added two photos of the back marks