Well regarding punctuality , being a regular travel i can say ..even if it starts @ 11;30 from BDCR also it will reach Secunderabad by 4:30-4:45 AM as it has huge slack throughout the route...
it generally arrived BDCR itself 10-15min and departs min 15-20 min late after loco reversal ..... its very rare that it starts On time from BDCR itself