The Council Tax (Exempt Dwellings) (Scotland) Order 1997

11.  An occupied dwelling–S

(a)which is not the sole or main residence of any person other than a student or a person falling within paragraph 10(a)(ii) above;

(b)which, when last occupied, was occupied by at least one student; and

(c)in respect of which less than 4 months have passed since the last occupation day.