Valid dates that don't start with a year are being indicated as invalid

[lat9]

... as shown in the following DbIo debug-log:

2020-09-23 16:07:57: formatValidateDate: (08-21-2019, datetime), DBIO_IMPORT_DATE_FORMAT = 'm-d-y', returning (). Parsed date: Array
(
    [year] => 
    [month] => 
    [day] => 
    [hour] => 
    [minute] => 
    [second] => 
    [fraction] => 
    [warning_count] => 1
    [warnings] => Array
        (
            [5] => Double timezone specification
        )

    [error_count] => 2
    [errors] => Array
        (
            [0] => Unexpected character
            [1] => Unexpected character
        )

    [is_localtime] => 1
    [zone_type] => 1
    [zone] => -75600
    [is_dst] => 
)