Again, I think you are making it more complicated than it needs to be.

How many users are you talking about?
If it is a small number, I would just tell everyone they have to be logged off their systems by x o'clock on Friday night. Then, from your server, copy all of the user files from the one server to the other. Modify your startup script to delete the current f drive and map the new f drive.

If it is a large number, you still do the same thing except I would add some sort of rsync process from the old pst shares to the new ones in case someone doesn't listen and stays logged in.

In either case, outlook won't have to change because it will find the pst files in the exact same location.

Does that make sense? Do the work from your server, not from a client script.

Regards,

Brad V