1. We can’t meet the deadline until our client approves X.
  2. We won’t be able to meet the deadline due to several issues concerning our application for the building permit.
  3. The building authorities have not approved our application, so we will not be able to make the deadline.
  4. We could still make the deadline if you submit the documents by Monday morning.
  5. We are not able to meet the deadline; could we ask for a two-week extension?
  6. The deadline is fast approaching. Could you give us a status report/an update on the project?
  7. By not completing the work by Thursday, this prevents us from meeting the deadline. (passive sentence, less direct)
  8. If he does not complete the work by Friday, we are going to miss the deadline.
  9. The deadline is too tight. Is there any way we could extend it for two days?
  10. We are really behind schedule; I am going to request a week’s extension.