Finally getting around to mounting my used GB and came across these along the way. Nothing valuable but noted in Gibbons.
Will upload close-ups if these are not too clear.
First one is the large white full stop after the value "4".
Second is the missing date and copyright symbol which came as the left stamp of a joined pair.



The nice bit is that I have soaked these off from paper myself, what other curios are lurking yet to be soaked or found.