Biometric Certification- 5 Days to mail
 

I just has my Biometric Screening done and have my biometric confirmation receipt. The form they gave me from UK Visas & Immigration states that I have 5 days from the appointment to mail my application package in. Is that 5 working days or 5 days total?

I am waiting for a letter (posted air mail) from the person who is letting us stay with him when we arrive in the UK. To meet the requirements for the accommodation portion of the application I have read that I need a letter from him with a wet signature. Not sure what to do now. Any suggestions?
Thanks again for your assistance.