AMCA requirement took 4 years to happen. The DRDO has shown three different models for this aircraft (MCA, then AMCA, now NGFA?) over a period of 5 years. The design work was once announced to start in 2009, now "scheduled" to start in 2011. The design takes 2-3 years alone. Building the first prototype takes 3-4 years, then testing (2-3 years), building one or two more prototypes (another 2-3 years), all this provided there is no scope creep and no funds crunch, not to mention all technologies are available at all times. IOC will take another year or two. All in all, first manufacturing will not take place before 12 years (earliest) to 15 years (more likely). Induction will take place in about 16-17 years - so let's say by about 2028, the first AMCA will be inducted into the IAF.
Anybody believing in any time sooner is definitely HIGH!