The definition of the openformula function ADDRESS says:
Constraints: Row >= 1, Column >= 1, 1 <= Abs <= 4; A1 = TRUE(). Evaluators may evaluate expressions that do not meet the constraint A1 = TRUE().
In the semantics section, the format is also described for A1 = FALSE(). It is not clear what the status of that specification is: If an evaluator evaluates an expression with A1 = FALSE(), is that evaluator required to follow the description given?