6. In paragraph 1 of Schedule 2—
(a)in sub-paragraph (4), for the words “or aircraft” there shall be substituted the words “, aircraft or, where it has arrived in, or is seeking to leave, the United Kingdom through the tunnel system, vehicle”; and
(b)in sub-paragraph (5), for the words “or aircraft” in the first place where they occur there shall be subsituted the words “, aircraft or, where it has arrived in , or is seeking to leave, the United Kingdom through the tunnel system, vehicle”.