@swekarl apologies about the order numbers. WooCommerce uses a job queuing system called ActionScheduler, which this plugin uses extensively for updating data in background jobs vs performing costly database inserts during a customer checkout for example.
ActionScheduler currently uses a Custom Post Type to store and process background job data, so each job inserts a new record into the posts table, which increases the order numbers – since Orders too, and their numbers are tied to the same database table.
A new version of ActionScheduler will be coming out soon that moves away from using the Custom Post Type so this will no longer be an issue. I realize that doesn’t fix your problem for you, but wanted to let anybody else who might read this know the cause and the solution that is being put into place.
Also just FYI, anytime you create a new page or blog post on your site, or if you use any other plugins that leverage Custom Post Types, your order numbers will increase.