Ah, so it wasn't revised for the '81 re-release then... have you compared the credits more close, none? I don't know, maybe there were typos or other people involved in the production missing that were added to the credits on later prints when the film became the huge hit, some typos have never been fixed to this day though so I don't know about that.

Those examples are also just a few of the differences, there is different spacing throughout the credits, from the moment John Barry appears to the end. I can check it, if someone else haven't already.