@frank18 ... OK, color me confused!
That "Edit" button shows in both the checkout_one_confirmation and ajax_checkout_confirmation pages and the plugin doesn't distribute the file /includes/templates/YOUR_TEMPLATE/tpl_checkout_one_confirmation_default.php.
From what I can see, reviewing the GitHub changes, that button was added back in August of 2016; perhaps you've made a template-override version that (somehow) got down-level?
Please advise.
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