Test pause is a good way of keeping a timed test on hold when your learners are not able to complete the test for some personal reason. To enable Test Pause,
Go to your mock test builder and head to settings
Click on quiz feature and scroll down till you see quiz pause.
Click on the check box next to quiz pause to enable the feature.
Voila! now your learners can pause the timed tests in midway and come back later, to it.