Facebook Feed XML and Discounts

Hi,
your plugin works very weel on our websites, but there is a strange behaviour that we hope you can help us to solve.

We manage our Facebook XML Feed with a third part plugin, Pixel Caffeine.

This plugin is able to write the sale price in XML feed for Facebook, but only if we generate the feed manually. If we apply the apply the automatic refresh of the feed (every one hour, for example) the sale price suddendly disappears! If we click on refresh button, it appears again!

We contacted the developer of Pixel Caffeine that said us:
“That behavior is really strange. The service that generates the feed is the same both when you create a new feed and refresh and refresh automatically from the scheduled cron.
Please, try to contact the developer plugin (= the developer of WooCommerce Discounts) and ask to ensure that the filters for the sale work properly during a cron task”

Hope my explanation is clear.

Thank you very much, regards,
MARCO