I would guess you can split the lines without help as that is very basic.
in reply to How to read each line of file into an array and split contnts of each line into array cells
Once you have done that, look at Date::Calc to help you determine the appropriateness of any given entry. Your date field will need to be moderately massaged to work, but that is also very basic.
Just look at Date::Calc on CPAN and read it... all will become apparent...
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