Having trouble replicating P6 schedule after import

All, I am managing a fabrication subcontractor who is delivering weekly schedule updates to me in a PDF and P6 XER file. I import the P6 file into my P6 software in a new EPS node with only this single project in the node. I use the "update existing" setting for all the project fields during the import. (not that this matters because I am not updating an existing project). I then open the project file and I am not able to replicate the same dates that are shown in the PDF file that I am provided with the P6 file. The activities that I show in my Primavera differ only slightly, 1 day on many activities. This leads me to believe it might have something to do with the work calendar settings and the number of hours per week that I have in my software compare to the software settings of the subcontractor's Primavera. (if he is using a 10 hour day and I have an 8 hour day, my software will bump activity finish dates to the next day or multiple days in some cases) What information should I ask for, from my subcontractor, to make sure I have all the calendar and work hour settings correct? He can take some screenshots and send them to me. If my problem and question are not clear, let me know.