12.—(1) Subject to any other statutory provision, where under a covenant (whether express or implied) more persons than one are—
(a)covenantors, the covenant binds the covenantors and any two or more of them jointly and each of them severally;
(b)covenantees, the covenant shall be construed as being also made with each of them.
(2) This Article applies only if and as far as a contrary intention is not expressed in the covenant and applies only to covenants entered into after the commencement of this Article.