Hi, and welcome to OFPEC
moved to more appropriate place
Is there a process for claiming an OFPEC tag that hasn't been in use for a long time?
In short, no such process exists.
Back in the day (surprisingly only 7 years ago though) it was decided that a TAG could never be re-assigned.
Arguments from both sides of the coin were equally good though, so it's a bit of a gray area I suppose.
I could personally maybe bend the rule a bit when it's really clear the TAG is a ghost.