Jualbo,
The Canberra engagement happened much later in the day approaching dusk. I don't have the precise coordinates for the task force at this time, but most likely the fleet was operating in roughly the same area as in the morning given the need operate strikes against positions on the Falklands and to provide adequate CAP coverage for them. It would have moved East at night; The raid was detected by Invincible on her 1022 set was at 120 miles closing. I believe the Canberras were operating from Trelew (perhaps you could confirm this). If so the graphic below would help explain.
The Alferez Sobral was sent sent to look for the downed Canberra crew when it was attacked by Coventry's Lynx with Sea Skua missiles. This was reported to be approximately 80 miles NW of the task force at the time. Coventry was on the northern most sector of the Type 42 Screen on that day.
