20:00 departure is not possible. A semi-fast local leaves CSMT at 20:00. It is chased by 20:10 leaving 12111 AMI exp, followed by 20:15 leaving NGP Duronto, followed by 20:25 leaving 17411 Mahalaxmi, followed by 20:35 departing 12809 HWH Mail. During this period, 12163 DR-MS leaves DR at 20:30 and 12151 group of trains leaves LTT at 20:35. This continues till very much 22:00. One train after another within a gap of just 10-15 mins. After TNA-DIWA new lines are commissioned, there will be some leg room to tweak the time table.