Yeah, I was going to add a note to that effect, but I seem to have forgotten.

Dealing with that isn't much more complex, you just need to use Time::Local and normalise the times to midday. That way you can be sure that subtracting 86,400 seconds will get you to the previous day. Like this:

use Time::Local;
use POSIX 'strftime';

# get today
my @today = localtime;

# normalise to midday
@today[0 .. 2] = (0, 0, 12);

# get normalised today
my $today = timelocal @today;

# get current day of week
my $dow = (localtime($today))[6];

# get last Sunday (day 0)
my $sunday = $today - (86_400 * $dow);

# get Tuesday (day 2)
my $tuesday = $sunday + (86_400 * 2);

# print Tuesday in a nice format
print strftime "Tuesday is %d %B %Y\n", localtime $tuesday;
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