I'm a GC on a small addition. The framing sub made some errors based on a failure to properly read the plans r take field measurements. After completing the corrections he then issued a change order which was not approved. After explaining that these were his mistakes to correct and in any event you cannot expect to get paid by issuing CO's after the work is complete, he has now sent a prelim notice despite the fact that he was last on the job nearly 60 days ago. My expectation is that he intends to now issue a notice of intent to lien. What is the best way to deal with this?