DynamoDB Mapper For Conditional Saves With More Than One Conditions

Question

I have been trying to use DynamoDB mapper for creating save expressions. I want to save a record iff

1. A particular attribute value doesn't exist. OR
2. That attribute value should be greater than a particular value.

So I have created an expression for it, but it throws IllegalArgumentException.

expected.put("date",
                new ExpectedAttributeValue(new AttributeValue()
                        .withN(Long.toString(date.toEpochMilli())))
                        .withComparisonOperator(ComparisonOperator.LT));
        expected.put("date", new ExpectedAttributeValue(false));
        saveExpression.withConditionalOperator(ConditionalOperator.OR);
saveExpression.setExpected(expected);

This is the kind of exception I'm getting.

java.lang.IllegalArgumentException: Unable to assert the value of the fields [version], since the expected value conditions cannot be combined with user-specified conditions joined by "OR"

I was wondering if I'm missing something or is there something wrong??

Edit

Looks like I couldn't use an OR operation between two internal conditions. Is it possible to do OR-ing in some way?? Thanks in advance.