GSAT-12
GSAT-12 was a communication satellite designed and developed by the Indian Space Research Organisation. It was the second satellite to be launched and placed on a GTO using PSLV. Satellite
GSAT-12 was considered to be a replacement of the aged satellite INSAT-3B. It provided services like tele-education, tele-medicine, disaster management support and satellite internet access. Payloads
GSAT-12 was equipped with 12 Extended C-band transponders. Launch
GSAT-12 was launched onboard PSLV-XL C17 from second launch pad of Satish Dhawan Space Centre on July 15, 2011. The tentative life of satellite was 8 years. Replacement and relocation 
While GSAT-12 was still operational a replacement satellite CMS-01(formerly GSAT-12R) was launched on 17 December 2020. GSAT-12 was relocated from 83°E slot to 48°E slot on 19 March 2021. End of mission 
In March 2023 GSAT-12 was retired from its operational service. After seven maneuvers to raise the satellite to a circular graveyard orbit, 390 km above GEO belt. References

GSAT satellites
Spacecraft launched in 2011
2011 in India