TEDBF brochure from ADA. Now that the wind tunnel model is in testing, I would expect some more refinement of the design going forward before more detailed design activities begin. Those talking about the possible absence of DSI intakes on the wind tunnel model of TEDBF, I think we may see a separate Wind Tunnel Model built for studying the TEDBF's intake design at a later stage. As of now they're focusing on freezing the configuration.
Targeted induction date into service is 2031, which is 10 years from now. To achieve that, the prototype will need to be in flight tests at least by 2026. At least 4-5 years of flight and carrier compatibility testing will be required before TEDBF achieves IOC.
The FCS will be a derivative of the FCS that is being developed for the Tejas Mk2 (which itself is a derivative of the FCS from Tejas Mk1). Both platforms have similar surfaces (leading edge slats, elevons, single rudder and canards) so it will definitely be using the Tejas Mk2 FCS as the baseline from which to modify it for the TEDBF.
Also there will be a lot of avionics commonality between TEDBF and Tejas Mk2. I would expect a very very high degree of commonality to keep development times as low as possible. Similar cockpit layouts, software for the avionics and systems. Would also leverage work being done on the AMCA for software and avionics plus systems both being twin engined fighters with approximately similar MTOWs.
Radar could likely be the GaN variant of Uttam AESA radar. (LRDE has recently fabricated a GaN plank which is the building block for beginning to assemble a GaN AESA radar prototype). Indranil's tweet confirmed this.
LRDE on the verge of realizing GaN based X-band AESA radar. 32 element plank is roughly 555 mm in length and 10mm in breadth. This is quite state-of-the-art.