As previously noted it is vital that appeals to the EAT are lodged on time and properly constituted (legal jargon for having all the necessary documents present and correct).
An easy way of getting this wrong is to miss pages out of a document accidentally. A document with a missing page is incomplete and will make the appeal invalid until the omission is fixed. If this happens after the deadline the appeal will be out of time.
There are any number of ways of accidentally missing out a document. Photocopiers are often to blame, particularly those with automated feeder trays that can all too easily swallow two pages instead of one. Sometimes the problem is a mistaken attempt at brevity – leaving out a blank page on the basis that it is unnecessary.
To labour the point: when filing a notice of appeal it is important to be very careful that all the required documents are included and complete. And it is sensible to do this at least a week in advance of the deadline, so you have time to correct any mistake that slips through.