Or, yet differently, if you want to score some software design points:

use DateTime;
use DateTime::Event::Recurrence;

my $thu  = DateTime::Event::Recurrence->
            weekly(days => 4); # Thursday
my $days = DateTime::Event::Recurrence->
            daily();
my $set = $thu->intersection($days);

my $it = $set->iterator(
   start => DateTime->today()
);

if(my $dt = $it->next()) {
    print "Next Thursday from today: $dt\n";
}
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