If each user is using a split db with their own fe and be, and each user's be could be on a network drive but may have different drive letter then you should use UNC path when creating the distributed fe as stated. Then they should not have to do any relinking. If the user isn't on the same UNC path, or that path differs once you start including subfolders, then you'll have to store each users be path in the user table as one of their attributes. Your startup code would then have to DLookup their path and pass the string to the relinking code.
You could also use CurrentProject.Path property in code - as long as each use is savvy enough to make sure the be and the new fe they download is in the same folder. Then the code would simply act as if the new fe and be is in the same location. I don't think you'd need UNC or a table of paths, or have to worry about drive letters.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.