we have a similar street sign issue on Hill Park Terrace, one real possibility is the sign makers were given ambiguous wording on the list they received so they went both ways to cover their bases?

fyi those signs probably run about $20-$40 each and probably take some time to make, that was the reason i never reported it (there's also the idea that the confusion was so minimal - in my admittedly imperfect estimation - that correcting it seemed unnecessary - the only reason i could imagine it would help is if you have a gps that can't auto suggest)