Airbus had predicted this a long time ago and one of the points in their trying to push AI into buying the Airbus A340 was "in the possibility/scenario of Air India merging with Indian Airlines, a common fleet will help reduce costs. ..."
The advantage of fleet commonality has been computed to $2000 per sector, in $ terms, this was done by continental as part of their fleet renewal programme. However this advantage is insignificant while taking into consideration SFC for a A343/5/6 against a B772/3/LR, hence you see multi fleet with most airlines around the world today.
Undoubtedly a good mix for AI the B787 & B777, considering its routes.
The Q ''challayega kaun'', some wizz kid IAS officer along with a hotch potch of employees, recruited over the years because of their allegiance to various Ministers.