Two more comments:
1. Alpha Lock: It only prevents retraction of the slats , not the flaps when you're in the AOA protection range.
2. My experience is that not the flap movement changes the Vmax indication on the PFD but the handle position. Whenever you move the flap handle, the Vmax indication immediately jumps to the new value for the selected setting. Other than the Vls which reflects the current situatiion at any given time. You can see that when you use various speed brake positions: Vls dynamically adjusts.