With 4 or more codes to fetch, the script will complain about using a cron job if disabled in the settings.
$noCron = false; // true=not using cron, update data when cache file expires false=use cron to update data
If the source of the data is busy, it could take 6 seconds to fetch the data for each code. Having 4 locations with 2 codes each, the processing time for the data download would be at least 48 seconds.
After the script finishes the processing, the index page will then proceed to load.
That's a lot of time to wait for the main index page to load so I highly recommend a cron job or a similar way to run the script at intervals.
As mentioned, the Windows Task Scheduler is very reliable and easy to set up.