The two signs don't mean the same thing, although I accept you got a bit confused. The first sign says all "traffic must turn left", with a qualifier plate below that gives exceptions to the arrow.
The second sign means "No Right Turn" with the plate below giving exceptions, with a No Left Turn similarly. These signs mean traffic must drive straight ahead and must not turn (left or right), the other sign means traffic MUST make a turn.
I suggest you submit reps on the basis that you have driven this way for 15 years at least, and it was a shock coming to this sign and you were therefore confused and drove straight on, (or turned right; you don't say which).
They may shoot themselves in the foot in their rejection, but unless they do, I can't see a win here at the adjudicators where the full PCN penalty is in play.