回复：小白兔，两分钱看过来：EB1-OR 180天换工作，

There is no explicit permanent job requirement in either AC21 law or the memos about the the law. However, the requirement could be implied in the clause "same of similar job". In fact, you do not have to secure a tenured-track job to satisfy this requirement. Any job without a definite terminating date is considered as a permanent job. A typical sencense for a regular job (permanent job) is "we expect him/her .... in this position indefinitely". Such a requirement is easily to be satisfied.