N139PB is reserved. Post-cancellation hold — if it isn't renewed, the FAA releases it on Nov 7, 2030 (in about 4.4 years).
This tail was recently cancelled. The FAA holds cancelled N-numbers before releasing them back to the public.
Reservations lapse more often than you'd think. Check back around Nov 7, 2030 — if the holder doesn't renew, it becomes available. See everything scheduled to free up in November 2030.
N139PB has been worn before. Past registrations from FAA deregistration records:
Tails one nudge away from N139PB that aren't assigned or reserved: