This little shape 49 pin dish has an early blue coloured dolphin back stamp and a small painters mark that my best guess is that of Christine Tate. Sometimes marks are squashed up close to the base rims on pots and can be harder to read. On this there's a clear T and a blob that I'm reading as a C. The other possibility is that the blob is an M, but thinking that this was painted by Tony Morris would be stretching it. Anyway it dates from about 1966 or '67.
A photo of this same dish taken before it joined my collection appears on page 86 of the Robert Prescott-Walker book "Collecting Poole Pottery"