Hi, I am working in china officially with EP & RP, try to extend L type for my wife

Tom, it's ok to extend your wife's L type at local entry and exit management bureau. The duration she acquires won't exceed the previous one. The required documents are her passport, application form, a recent passport photo, temporary accommodation registration and a local bank account which contains at least CNY21000 or 3000USD. Please note that extension should be submitted at least seven days before her current one expires.