BTEC level 3 Subsidiary Diploma for a year?

Sorry if this is a bit confusing! Orginally, I planned on taking Law, Physiology, Health & Social Care and the Subsidary Diploma which is in Applied Science. However, I planned on doing this with the intention of dropping the Subsidary Diploma after one year thinking I would still get something for it. On the college website it states that the course is for 2 years but me being stupid still assumed I could do it for 1. Do you know if this is possible? I've seen that for one year you get a certificate and the second the actual diploma? Thank you for your help.