Barring temporary diversions, TN never ran via Kazipet in its regular schedule.
I've attached scans from the 1978 TT for the BZA-BPQ and HYB-KZJ-BZA sections. You can see that TN and the Cochin Jayanti Janata skipped KZJ while others like GT, MAS-NZM (precursor of VSKP link express) and GK called at KZJ and reversed.
The...
more... IRFCA gallery has the TTs from 1977 -
click here (TN didn't halt at Warangal either, in 1977). These also show that TN did not reverse at Kazipet.
I can also share TTs for all years between 1977 and 1992 (except 80 and 82) for more details about this.
BZA-KZJ electrification was complete by the end of 1987 and KZJ-NGP electrification was completed by early 1989. 1988 was the only year when TN may have needed a diversion via KZJ for loco change, but the April and November TTs from 1988 show TN skipping KZJ.