Accepted claims for an extension give you another 14 calendar days from the original submission deadline to submit your work. You'll need to submit your work to the correct link on Moodle - if you're not sure which link to use, check with your module leader.
‘Calendar days’ means every day of the week including Saturdays and Sundays, except for university closures days such as public holidays and Christmas closures. Full details of term dates and university closures days can be found here.