The only good thing about the 2pm departure ex-Heathrow (in defiance of the hit and miss approach to landing) is that if you were lucky enough to hit the ground on schedule is that you avoided the dire nature of Bbangalore;s notrious traffic. The 5am journey in from the airport is the only sane time to arrive.
On the other hand, the later departure ex-BLR, offers the chance for a morning lie in instead of the horrific 4am wake-up call and the dilemma of worndering whether to stay up or go to bed.