Are both sectors on the same PNR, I wonder...if they are, (a) how on earth did they manage that and (b) in that case 9W will have to shoulder the responsibility for any delays. If that works in your favour (a possible extra night in BOM), zig2, I say go for it and stick to the original plan with 2 hours connection.

In December 2009, I did MAA-BOM-SIN on 9W470-9W012, which had a 2h20m connection time in BOM. Though the flight left MAA on time, BOM arrival was a bit delayed due to traffic, yet I had a bit of time to go to the lounge in BOM International.

I'd say it all depends on how much of delay the BLR-BOM flight USUALLY encounters.