In practical terms, I’d say you’re not mistaken. The difficulty using up your last bit of resin has frustrated several users, including me (and inspired a small cartoon).
As you noted it can be worked around by waiting for the override message to come up. I think if you start with a cartridge the system already knows is completely empty, it may come up nearer to the beginning of the print.
You might be interested in this thread (specific to the Form 2 but the issue is the same):