6.—(1) This regulation applies to any unit of property (“relevant property”) which by virtue of section 64(1) of the Act comprises separate hereditaments solely by reason of being divided by a boundary between charging authorities.
(2) Relevant property shall be treated as one hereditament and, subject to paragraphs (3) and (4), as situated throughout any relevant period in the area of the charging authority in whose area is situated that part of the property which would but for this regulation be the hereditament appearing to the relevant valuation officer or officers to have, on the relevant day, the greater or (as the case may be) the greatest rateable value.
(3) Relevant property which on the relevant day includes any land falling to be valued as provided in regulation 5(2) shall be treated as situated throughout any relevant period in the area of the charging authority in whose area is situated the part of the property (disregarding any land which falls to be so valued) which would but for this regulation be the hereditament appearing to the relevant valuation officer or officers to have, on the relevant day, the greater or (as the case may be) the greatest rateable value.
(4) Relevant property which on the relevant day consists exclusively of land falling to be valued as provided in regulation 5(2) shall be treated throughout any relevant period as situated in the area of the charging authority determined by lot by the relevant valuation officer or officers.
(5) Where for the purposes of paragraph (2) or (3) the rateable values of the parts of the relevant property appear to the relevant valuation officer or officers to be equal, or where there is more than one relevant valuation officer and those officers do not agree as to which value is greater or the greatest, the charging authority in whose area the hereditament is to be treated as situated shall be determined by lot by that officer or officers.
(6) In this regulation–
“relevant day” means a day on which a local rating list must be compiled or, where the hereditament referred to in paragraph (2) would first fall to be shown in such a list for any day later than the day on which such a list must be compiled, the day on which it would first so fall to be shown;
“relevant period” means the period beginning with the relevant day and ending when a new local rating list is compiled; and
“relevant valuation officer” means the valuation officer for a charging authority within whose area any part of the relevant property is situated.