South Pacific Colour Glaze

This backstamp is different to the two in the gallery, no Roydon or British on these two side plates... what's this colour? cocoa?.

Kat,
It says British after colours doesn't it?

Well the Roydon South Pacific was only sold at McKenzies, so is the South Pacific British a different pattern, or the same? The backstamp is different enough to add to the Gallery I reckon.
I will await your opinions

Just an opinion as I am out of my comfort zone here but is production date the key.

1 SP British as in gallery, (whenever the clean colour glazes were first used, ca mid-late 50s) followed by
2 SP British as above (ca late 50s, early 60s), with the inclusion of "guaranteed fast colours", followed by
3 Roydon SP as in gallery, with "acid and detergent" etc (ca mid-60s).

The big picture gives us colour glazes as Caribbean, South Pacific, Capri, and Colour Glaze: South Pacific may have been taken out of that general pool of names and given to the Roydon brand by arrangement with McKenzies.