You always need to sleep this amount before running, not adjusted for local time zone

#!/usr/bin/env perl
# snooze.pl
use strict;
use warnings;
use Time::Local;

my $min  = 60;
my $hour = 60 * $min;
my $day  = 24 * $hour;
my $week = 7  * $day;

# First W 10 AM
# Epoch is Thursday 00:00:00 Jan 1, 1970
my $w = timegm(gmtime(6 *$day + 10*$hour));

# Upcoming Wednesday 10AM
$w += $week until ($w > time);

my $diff =  $w - time;
print $diff
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At the prompt

server$ (while :; do sleep $(snooze.pl); doJob.pl; done &)
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