A Microsoft file hosting and synchronization service.
Hi,
Welcome to Microsoft Community.
Based on the detailed description, we totally understand your scenario that you need to kind of update the shared PDF and keep the original sharing link/URL. In this situation, we are sorry to convey that your understanding is correct, and the PDF files are not able to replace/update another copy but keep the same URL.
Really sorry for all the inconveniences it may have caused on your side. A suggestion I'd like to share with you is to share a Word document with others but in 'Read-only' permission so that the file won't get edited by others but you will be able to edit it anytime and let people always get the latest version of your tour book.
For the limitation of PDF files, kindly submit your feedback to the related product team and let them provide a better sharing experience with PDF files in OneDrive. How do I give feedback on Microsoft Office? Really sorry that forum engineers here have no resources to the building of features in Office.
Appreciate your kind patience and hope a nice day for you!
Best Regards,
Mia