The teacher had the appropriate documentation from the previous post; visa and expert certificate. The documents were given to the new employers who coming from the same province, fell under the same bureau. The problem arose when the bureau allegedly misplaced the old certificate which meant that the new school had to fill in a completely new form (this is how it was explained to me). This was time consuming and become of secondary importance to other matters. The teacher thought everything was fine and dandy (public school) and didnt ask any questions. Then when the teacher asked about the visa the problem surfaced.
Eventually the matter was resolved but the teacher paid the fine. Willingly but bitterly.