If there is a constraint, it will be communicated (irrespective to the place/division).
Even, while replying to some of the representations made by Hon'ble MP, Kurnool on 25.09.2018, General Manager/South Central Railway had replied that - Due to lack of Primary Maintenance facilities at Kurnool, it is not feasible. It was also replied that maintenance slots at Tirupati coaching depot are saturated.
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But later, Primary Maintenance of Padmavathi Express was shifted to Tirupati (from Secunderabad).
I believe this will help you in understanding the case with other places & divisions (KRNT/HYB) as well, while you comment about Nandyal/Guntur division.
Moreover, if you are so confident about the political push, you may try for shifting Primary Maintenance of Simhadri Express from Guntur to Visakhapatnam. This will pave way for extending Simhadri Express upto Dhone (duly integrating with GNT-DHNE-GNT Passenger/Express).