TBTA might be in the process of migrating away from their conventional analog. Have heard TGs 9142 and 9143 (I believe 9141 too) all with sporadic TBTA related traffic and radio testing in the past few weeks.
Have heard 9139 (it's in the database) being used in regards to the multi agency task force cracking down on license plate fraud.
That would be cool if they switched. 9139 and 9140 are in the DB as MTA BTO Spec Ops. Ill add the other unknowns into the wiki. What site did you pick them up on? im assuming metro 25?