Actual vs Existing Credits

Many times I notice that existing credits do not match actual screen credits and I know this is not new news. Some, for instance, in the Camera Dept seem to follow certain patterns, almost like there's an unofficial protocol where no matter what the actual credits say, the entered credits follow this pattern. An example:

Actual credit: b camera operator

Existing credit: camera operator: "b" camera

This existing credit is the "default" I'm referring to.

Another example:

Actual credit: 2nd 2nd assistant director

Existing credit: second second assistant director

(another "default" - changing 2nd to second)?

If there is some unofficial protocol for some common types of credits, shouldn't it be spelled out in the Help, something akin to Help example 'translation' to 'translator'?

In any case, my main question is, absent these protocols, is it all right to change these existing credits to the actual credits, including their abbreviations and punctuations, unless they're covered to the contrary somewhere in the Help?