Aside from the 1 series 3 door, 2 series GT/AT and future X2, 4 gran coupe & 6 gran coupe, it's odd numbers have 4 or 5 doors and even numbers are the coupe (2 door) version.
FTFY
You missed the 2 Series AT as well.
God awful looking thing, so I can't blame you.
Updated, so tbh it's not really a rule at all.
@Sam_w started
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FTFY