Returning means, returning to base. Generally when it is returning from NFR to SWR, via-ER,SER,ECoR,etc, every zone may use the loco. ER used it for atleast 10 days (with a checkup at UDL/DLS), SER used it for no time,it just passed through SER to Dhamra Port, then ECoR used it for some days,which I didn't trace. Now this "used it" means,it hauled goods train for in a section, running UP/DN several times (and u might had spotted it during that time). So what I wanted to mean that, this loco came to NFR for duty, during return to its base at KJM/SWR, it did duty at many zones. But it was actually being returned back to its home shed after 2-3 months of out-zonal duties. And the loco is currently at KJM, so it surely was returning.