I've gone back through the order number records and found that
All using the Order Number Customizer extension by XTENTO.
Starting with the release of Magento Commerce 2.3.2, Magento will assign
The content on this page is for Magento Commerce only.
Change any starting numbers & prefixes for all types of store documents such as invoices, orders, shipments, credit memos with Magento 2 Custom Order ...
As it is they are in a random order, which often changes altogether when I add a
Customize your Magento order numbers and all other sales related numbers. The number format can be
http ://www.magentocommerce.com/products/bug-tracking/issue/ ...
The extension allows you to change Magento order numbers and other
Magento 2 Custom Order Number extension changes the order, invoice, shipment