Where the holder of an on-licence or a club licence for any premises also holds a special licence designated as an on-site special licence for the premises, the holder can at a time when the sale of alcohol on the premises would otherwise be unlawful (whether by virtue of a provision of this Act relating to licensed premises or licensed premises of any kind, or by virtue of any condition subject to which the on-licence or club licence was issued) sell or supply alcohol, for consumption there, if it is sold or supplied—
(a)
to people attending an event described in the special licence; and
(b)
in accordance with the special licence.