The IAF agreed to buy 83 Mk1A at Parrikar's prodding.
Once again, no. The IAF was always going to buy 83 more. They placed a hold on more orders until a new configuration was confirmed based on their maintainability evaluation. Parrikar only happened to be the RM at the time.
The GoI initially agreed but later decided to scrap SEF altogether. The IAF responded by proposing a substantial upgrade (aka MWF) of the Mk2 design which until then had been envisaged as a modest Mk1 ++ with minimal design changes (1m airframe plug, wider air intake, more fuel and weapons, new radar, etc)
IAF did not propose anything. They wanted SEF tender, but ADA promised to boost the LCA's design to sideline SEF. The IAF agreed to it 'cause the Mk2 was a superior design compared to SEFs.
Look at the dates.

MWF was already at its new configuration when Parrikar was around.
This is how far back everything goes. IAF releases their report, HAL gets around to fixing it. ADA realizes Mk1A relegates 2014 LCA to nothingness, so they get around to designing Mk2. By 2019, the Mk2 design surpasses M2000, and the IAF becomes comfortable with it. IAF backs out of SEF demand in 2019 and switches sight to TEF, aka, MRFA. No Parrikar involved in the beginning or the end.
The IAF had reservations about HALs ability to deliver Mk1A on time. It didn't want a 'three legged Cheetah' as characterized by a serving ACM.
The 83 Mk1A order was a result of direct intervention by GoI.
No. the three-legged cheetah comment was made in 2011, when ADA pushed an IOC-1 model. The IAF refused to accept that, and waited for IOC-2, which happened in 2013. This is when production for the first 20 was cleared. Then came the production for the next 20.
The remaining 83 were always meant to be ordered. It was guaranteed as part of the original program. HAL had already built the production line for the follow-on 83 alongside the first 20. Meaning, HAL was guaranteed to get 83 more long before Modi became PM.
The 120kN TF for AMCA alone is a 10 yr plus effort. Its why the IAF settled for the F414 powered Mk1 model. You're not getting a 6G VCE engine in 5-7 yrs.
10 years is for an operational engine. Getting the engine itself takes 3 years. Unlike aircraft that comes in bits and pieces, engine has to be in its final configuration right from when ground testing begins. AMCA's ground testing and first flight are expected 3 years after contract. And 6th gen's ground testing and first flight is 5-7 years.
Post that comes roughly 5 years of flight testing on two sets of FTBs. One on the MKI FTB, the other on the main fighter. Then comes production. That's 3+7 years.
So we will see 6th gen engine ready for testing in 5-7 years and then it will take another 7 years to get an operational engine. So 2036 for 5th gen engine and 2040 for 6th gen.
Standard engine design from scratch is 25 years. 10-15 years for material design and 10 years for system design. Our development is compressed because France is gonna supply the material design.

