Good Morning Heather,
Sorry, but I was only drawing from my schoolboy history ... I know virtually nothing about Bohemian glass, porcelain and so on. I know a little bit about Staffordshire and Derby pieces because they are so close to home.
Wendy has sound advice, she seems to have done her homework. I tried to pin down that particular back stamp, but gave up. It's definitely post 1918, and maybe even after 1927.
It is hard to tell, but it doesn't look transfer printed and then painted, it does seem to be 100% hand painted. It is a large piece which may help, and it is a pretty piece. Good luck with it!