There were other errors, and were not even related to vertical signs, but there were some ground signs that were labeled wrong. Those I considered real errors (strange you didn't noticed them, and noticed this one instead), what you are reporting is really minor comparing to what was fixed already.
If not, then consider the fact that the default FS library already contains the correct sign and, maybe, your team can use their "Dev.-Wizardry" and point the mapping-feature to the already existing sign in the default FS Library instead.
We might look into this, provided that it wouldn't look to out of place together with the other signs. Only the texture, of course, we'll keep using our 3d model.
However, we would ideally need a little bit more things to do, before releasing another update. Right now, first priority is to to the FS9 version of the update, second priority is to do the other 2 Hawaii airports.
We consider PHNL to be reasonably stable now, and the comments we are getting so far about the update, only confirm this. Which doesn't mean the scenery can't be improved: everything can be improved forever, for that matters, and it will never be perfect in any case.