Condless

WooCommerce plugin that sets default attribute for variable products automatically if only 1 option is in-stock.
<a href="https://en.condless.com/default-attributes-for-woocommerce/" rel="nofollow ugc">Documentation</a> | <a href="https://en.condless.com/contact/" rel="nofollow ugc">Contact</a>
Variable product of T-shirt with color attribute (White/Blue/Black) and size attribute (S/M/XL): 
If only Black T-shirts are in-stock: default color (Black), default size (none). 
If only Small T-shirts are in-stock: default color (none), default size (Small). 
If only White and XL T-shirts are in-stock: default color (White), default size (XL).
<h4>How It Works</h4>
<ol>
<li>Before product variations is displayed to the customer, the plugin will check each attribute, and if there is only 1 in-stock option it will be set as the default.</li>
</ol>
<h4>Features</h4>
<ul>
<li>Stock: Set option as default when it’s the only 1 in-stock.</li>
<li>Per Attribute: Set specific option as default in all products with that attribute (from the Edit Attribute screen)</li>
<li>Top: Set as default the first option of each attribute.</li>
<li>Out of stock: Disable out of stock variations.</li>
<li>Add to Cart button: In archive pages display for variable products the attribute name instead of: “Select options”.</li>
<li>Select options: In single product pages remove the select options text if default attribute is set.</li>
</ul>

Default Attributes for WooCommerce

WooCommerce plugin that sets default attribute for variable products automatically if only 1 option is in-stock.

Devtard

This plugin overrides default date and time of edited posts with dynamically calculated custom values. This is useful especially when scheduling posts; the plugin can, for example, automatically generate new post dates by incrementing the current most future post date by a specified number of days.
Calculated custom date and time will automatically replace default values after clicking the “Edit” link next to “Publish immediately” in the post editor’s Publish module.
<h4>Features</h4>
<ul>
<li>Date/time values usable as a reference: current date/time, oldest or most future post date/time; specific time of day</li>
<li>Date/time of reference can be increased or decreased by a specific number of days/minutes</li>
<li>Configurable post types and statuses of analyzed and affected posts</li>
</ul>
See <a href="https://wordpress.org/plugins/automatic-post-date-filler/screenshots/" rel="ugc">Screenshots</a> for more information.

Automatic Post Date Filler

Automatically sets custom date and time when editing posts.

Default Attributes for WooCommerce vs Automatic Post Date Filler