Since the regulations for rear-view mirrors are different in every country and will also change in the future, it makes sense not to commit to a fixed solution (mirror or camera), but to offer both systems for retrofitting. It could work like this:
1. On the right and left, as in the prototype, cameras are attached to the side arms, a camera for the central rear-view mirror is installed at the rear.
2. The three monitors for the rearview mirror cameras are optionally available. The central computer has three video outputs (e.g. HDMI) and there are cable channels and mounting options.
3. The three video streams can also be placed on the central monitor. Perhaps it even has better usability and is legally permissible in the future, then you can save yourself the extra monitors.
4. As long as cameras are not permitted, simple rear-view mirrors are attached to the arms, as known from campers; The mirrors cannot be adjusted remotely and have no heating, but in exchange the system can later be switched to the aerodynamic camera-only system.

Hi OceanDragon, I am from Germany 🤓. AFAIK, here and in Europe it is not allowed YET, see https://www.gesetze-im-internet.de/stvzo_2012/__56.html (german). Wether Aptera is classified as a Motorcycle is another topic (see the discussion about the dimensions).