after all this, my flight from BLR to LHR was cancelled due to the incoming flight being diverred to MAA (Chennai ) and BA not planning a slot back to blr in time.
I got an Airport Upgrade offer

Int he midst of EU261 claim for this... sloppy ba was still sitting in MAA when other diverted flights were heading over to BLR

After several hours of waiting we were rebooked on alternate flights

On the bright side we had 2 breakfasts in the lounge haha !