1. Almost. V.a.prot and V.a.max take account of current load factor (LF).
To correct your quote "But he/she pulled the stick, the LOAD FACTOR changed ---> V.a.prot moved up the scale to a speed that would now (with the big LF) result in.... Alpha protection AoA"
I am not aware of athr disengaging below Vls... do you have a reference for that? What does disengage is the autopilot, at alpha.prot +1°
The high AoA protection works by reducing pitch attitude only. This is ELAC control, Athr has nothing to do with it. However Athr, when engaged will always try to maintain target speed. Min target speed is Vls, so when engaged it is always trying to maintain a higher speed than v.a.prot anyway.
Also, the athr is limited to how far advanced the levers are. so if you have them near idle, with athr on, maybe it cannot even maintain Vls. Normally they are in CLB detent, giving the athr authority to command anything from idle to climb thrust.
2. Because Vls doesnt change with load factor, it stays constant, while V.a.prot and V.a.max shoot up the speed scale. For a brief moment, V.a.max is above Vls.
3.The levers are not back driven, so they stay where the pilot put them.
The whole sequence breaks down...
Athr on, speed mode, target 165kt selected.
Vls 135kt, constant.
Pulls stick back, big LF generated.
Airspeed decreases and V.a.max shoots up. Athr still targetting 165.
Airspeed and V.a.max meet at 158kt, and the ELAC forces nose down to keep AoA at V.a.max
A.floor activates simultaneously. Thrust goes TOGA.
Pilot relaxes the stick, allowing LF to decrease, V.a.prot/max go back down.
No longer in A.floor, thrust still in TOGA, FMA changes to TOGA LK
Pilot pushes instinctive disconnect, Athr disengages. Thrust now manually controlled.
Pilot pushes the Athr button to re engage. It engages, in THR LVR mode which indicates thr levers are below the CLB detent. Target speed now 165kt.
Pilot puts levers in CLB detent, FMA changes to SPEED