I would prefer to generate the timestamp in Perl rather than using backticks. One possibilty (among many):

my $date = POSIX::strftime "%Y%m%d", localtime;
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And what you totally disregard is error-handling.

Your get could fail (e.g. no internet-connection), your parsing of the page could fail (the website changed it's layout) and your open could fail (some permission problem maybe).

You should handle these conditions and report appropriate errors, rather than fail silently and maybe loose the history of your meteoric raise...