The early stamps of Bhopal hold more nice varieties than you could shake a stick at. Each position on the sheet was drawn by hand onto the lithographic stone, usually by printers with a fairly limited knowledge of English (though their Persian was excellent, when they were allowed to use it).
The correct inscription around the edge was H(er) H(ighness) Nawab Shah Jahan Begum, However, the printers tended to get into trouble with it. Here is an SG54e (the 1886 ˝ Anna green) inscribed 'NWABA' instead of 'NAWAB':

In the 1890 8 Anna (top value, equivalent to about 8 US cents at the time) SG 68a

the printer omitted the 'S' of 'SHAH', apart from being a bit wobbly with the English altogether.
In 1901, the old ruler died, and was succeeded by her daughter Nawab Sultan Jahan Begum. The new reign produced a new set of stamps, free of any English spelling errors.
But in 1903, it was decided to overprint the remaining stocks of the 8 Anna stamp with a red Persian 'S', as the initial of the new ruler. There were both long and short versions of the S:
Long:

and short

For some reason, Gibbons doesn't separate these; it just makes them both SG 99. They're both quite scarce, though.