This isn't to say that you shouldn't apply though.  For instance, perhaps your 1:1 is from Saint Andrews, Oxford, or some other highly rigorous program, and you have many other academic accolades you can lean on.  And perhaps your leadership experience via summer internships, campus activities, and more is well above average, etc.  

Of course, if you felt you could retake the test and boost your score before the deadlines, it might be worth it.  If not, you can take your shot and always reapply as a regular candidate down the road after working for a few years.

Best of luck!