* Tweak - Exclude pending orders when checking the maximum number of orders per day/time frame.
* Tweak - Check the maximum number of orders allowed when validating a delivery date in the checkout form.
* Tweak - Tested compatibility with WC 4.9.
* Fix - The setting "Number of orders" was not being saved when entering a zero value.
* Fix - Deactivate a delivery date/time frame in the calendar when its maximum number of orders is reached.
* Fix - Fixed `array_merge()` warning when adding a product to an active subscription with the "All products for WC Subscriptions" extension.
