except that Premiere in its infinite wisdom has decided that ALL the clips in the Project need to be relocated!
That is not normal at all and I suggest you broke the links to more files than you suggested by some means or other.
Network resources are easily "broken" and it is not recommended practice.
PPRO will notify only of broken link files. The others remain linked.
Generally when relinking...re link to one and the others in that location will follow in automatically.
If your files are scattered randomly....thats an organisation issue that only the editor can sort out by relinking everywhere.
Is there a way to make Premiere "rescan" for the files using the file locations it already has stored in the Project file?
That is exactly what it does every time you open a project. If anything isn't in the same place, it asks only for those missing files.
Thanks for the prompt response! It is indeed not all files but some, I see now. Must be network linked, as you've said (not intentionally).