According to me, demand by passengers are right.
From last 75 years, it was departing from PF 1.
The main thing is more than 50% commuters are daily travelers which are leaving from Pune attending office in Mumbai and coming back to Pune in the night.
If the train departs from PF 1, they can easily catch it even though they reached station little...
more... bit late as direct entry to PF 1 from multiple entrance.