After the expiry date, a learner's course training is void and they need to repeat the course to remain compliant. The expiry date is calculated using the Training interval setting — to learn more, see How do I set a course training interval?
By default, the expiry date is shown. This is a global setting that applies to all courses, and it's one of the certificate settings.
Step-by-step instructions
Go to Settings.
In the GENERAL section, click Global settings.
In the CERTIFICATES & TESTS section find Expiration dates and choose to hide or show it:
To hide expiry dates on certificates, select the check box.
To show expiry dates on certificates, clear the check box.
Click Save changes.