Tata Coffee bought Asian Coffee from Rajendra Challa, erstwhile promoter. Even after starting from scratch again in 1995 they have built CCL Products which sells 2.5x more than Tata Coffee in the global markets even when Tata had acquired Asian Coffee and had a head start.
The incentives end in 2020. A plant takes 2-3 years to be complete. Even in the latest communication from Tata Coffee management they are still contemplating the proposal at a committee level. The work on construction hasn't started. When their plant starts the tax holiday will be over and they will have reduced tax rates like other players. This speaks a lot about how prepared the management is when they take so long to take advantage of an incentive
Read about the coffee crisis in Vietnam in 2013 when in a single year 50% of the firms exporting coffee had to close their business because of oversupply. I think CCL knows what it is doing because they know that its an oversupplied market
They have mentioned of a 5% market share excluding Nestle. You can rework your calculations
There is one company in Vietnam which is 20% of the market. It is the Intimex Group. There are companies in Brazil & Columbia but they are not a direct competition because they supply Arabica and CCL is mostly into Robusta. Infact Vietnam & Indonesia are the major markets for Robusta beans so those are the only two markets which should concern
The margins have gone down because the company has started to get contracts from new clients which has reduced the blended margins. Also first two quarters are lean period hence to maintain volumes they have to sell at lower prices.
I think you should go through the concalls for your answer on this
Start reading more about the global coffee market. You will get your answers