As far as I know there is no simple way to relieve the licenses. You can
remove the machine names from the table, but the licenses remain held. Of
course, in hind sight, you should remove JDE from the station and re-deploy
it once the rename is completed.
The way we have tackled a similar situation is to use a free workstation,
name it to one of the old netbios names, deploy JDE then uninstall. Do this
for each of the old station names. This frees up the licenses.