See also bug#115879 (concerning NOT).
OR and AND are specified as the names of logical functions.
Without a respective specification OR and AND can also be used as operators.
There are additional inconsistencies.
Assuming A1, B1 are logical results e.g.
= A1 or B1 is rejected reporting Err:509 and not recognising "or" as predefined while
= (A1) OR (B1) is accepted and working.
OR and AND logical operators are not documented in the help of LibreOffice unless logical functions OR() and AND().
Best regards. JBF
AND and OR as a non-function binary operator is an undefined behaviour accepted for legacy reasons. We probably should get rid of it.