Can we choose what page of the PDF is generated as the thumbnail?

Does the plugin auto generate a thumbnail image based on the first page of a PDF? Is there a way to control which page the plugin uses to generate a Thumbnail? Reason I ask is because I have a client who is creating home listings and they have a PDF Spec sheet that goes with each listing. I want to auto generate the page that they show the floor plan and it’s not the first page of the PDF. I can just tell them that the thumbnail that gets generated is the 1st Page of the PDF? Let me know.