File downloading help in perl

Im trying to write a perl code to do the following task.

I have a website which is located in a diffirent country.
I want to download a file from that site everyday.
The file name keeps on changing everyday.
say the file name is CTP-latest-5.3.0.37.iso
next day it may change to "CTP-latest-5.3.0.38.iso" or remain same.

I want to download only if the version number (ie. 38 in above example("38.iso") is not the same from last sucessful download or else dont download.

Im very poor in perl, can someone help me on this ?

i tried with

#!/usr/bin/perl
 
use LWP::Simple;
 
#-- fetch the zip and save it as perlhowto.zip
my $status = getstore("http://star.mywebsite/CTP-LATEST-4.4.4.37.iso", "CVP-LATEST-5.3.0.37.iso");
 
if ( is_success($status) )
{
  print "file downloaded correctly\n";
}
else
{
  print "error downloading file: $status\n";
}
 

This works fine in downloading the file, But I need to have a check on version number. So I want to download only if the version number has been changed from the version number of previous successful download.

one idea is if we want to download "CTP-LATEST-4.4.4.37.iso" but the file is not available the download fails and we catch the error and we dont increment the value "37" however we are trying with the same value ("37") tommorow. so if ....37.iso is available tommorow then we download and increment the value 37 to 38.iso and store it.

thank you for your time.