In fact the tail if the ‘G’ is very variable in these early bronze pennies, many in my collection have these curved sides and some the more rectangular, but whether due to die wear or a formal font variation I don’t know. Perhaps proof coins, if from unworn dies, might clarify. Clearly the ‘G’ repair punch used here had the curved sides, and thus differing fonts on one coin is quite possible.
Oh, and congrats on joining the VIGTORIA club, Richard. One of my favourite errors.
Jerry