1. Load Factor is the vertical g force the aircraft experiences. (Lift/Weight).
2. ELAC controls pitch. Athr controls thrust. The ELAC will only need to pitch down to avoid stall if the autothrust is insufficient to accelerate the aircraft. The autothrusts target is higher than V.a.prot or V.a.max... they are both moving to accelerate the aircraft.
It would only be a problem if their targets were in opposite directions.
Practically, the only was to activate this protection is to 1. disengage autothrust and use low thrust, or a steep climb to reduce speed. 2. Keep autothrust on, but retard the thrust levers far enough back that you restrict the autothrusts authority so much that the aircraft reduces speed even though autothrust is giving its max thrust. 3. Pull back on the stick so hard that the V.a.prot/max go above your airspeed.
3. Quoting FCOM-DSC-22-30-90-GENERAL
"The autothrust (A/THR) is a function of the FMGS, it includes two independent A/THR commands, one per FMGC. Each one is able to control the thrust of both engines simultaneously through two Engine Interface Units and two Electronic Engine Controls (IAE engines) or two Engine Control Units (CFM engines). Only one FMGC controls the active A/THR, it is called the master FMGC."
So the Athr is a part of the FMGS. FMGS knows the target speed (Managed or selected), and current speed. The ATHR part then works out how much thrust it wants, and sends this to the EIUs, which in turn tell the FADECs, which work out how much fuel to put in the nozzles.
Separately, the FMGS calculates the pitch required and sends this to the FD
Another quote, this time about how the FD pitch mode and Athr mode relate.
FCOM-DSC-22-30-10-INTERACTION BETWEEN AP/FD AND ATHR MODES.
"The AP and FD pitch modes can control a target SPD/MACH or a vertical trajectory, and the A/THR mode can control a fixed thrust or a target SPD/MACH. However, the AP/FD and the A/THR cannot both control a target SPD/MACH simultaneously. Therefore the AP/FD pitch modes and A/THR mode are coordinated as follows:‐If an AP/FD pitch mode controls a vertical trajectory, the A/THR mode controls the target SPD/MACH.‐If an AP/FD pitch mode controls a target SPD or MACH, the A/THR mode controls the thrust.‐If no AP/FD pitch mode is engaged, the A/THR mode reverts to controlling the SPD/MACH mode. In other words, the selection of an AP/FD pitch mode determines which mode the A/THR controls.
Go ahead Ill see if i can help.
What makes you so interested in these things?