An applicant may inadvertently fail to submit the correct specified application form and thereby also provide the wrong fee payment or none at all. An applicant may also fail for one reason or the other to have their biometrics taken within the required time limit. These errors and failures may ultimately result in invalidation of a timely submitted leave application and therefore rejection with the result that such an applicant becomes an overstayer. An invalid application does not extend leave under section 3C of the 1971 Act (as per Iqbal & Ors, R (on the application of) v The Secretary of State for the Home Department  EWCA Civ 838, mentioned below). Section 3C does not extend leave where the application is made after the applicant’s current leave has expired.