If you are printing your contract note off the Halifax website, I'd take in into your local branch and get them to stamp it. The shareholders club rejected my original application 2 years ago and my renewal last week on first attempt but were fine once I'd had the documents stamped.
Rather than post or fax the paperwork I scanned my application and proof of ownership and emailed it to them. The first attempt I got a reply within the hour saying that the documents were incorrect. When I had corrected it and resent it I received confirmation that I'd been successful the next working day and I was emailed my temporary certificate 2 days later.
Don't forget to write "I accept and approve" before your signature on the application form as well.
Hope this helps
Mark