“applications for extensions of time...are commonplace and the approach to be adopted is well established. As a general rule...the tribunal asks itself... (1) What is the purpose of the time limit? (2) How long was the delay? (3) Is there a good explanation of the delay? (4) What will be the consequences for the parties of an extension...? (5) What will be the consequences for the parties of a refusal to extend...? The Tribunal then makes its decision in the light of the answers to those questions.”