What happens when there is a valid alternative proposal?
Uruguay
Constitution of Uruguay (Constitución de la RepúblicaOriental del Uruguay)
http://www.refworld.org/docid/3ae6b5600.html
Article 331.
The present Constitution may be amended, inwhole or in part, in accordance with the following procedures:
a)Upon the initiative of ten percent of thecitizens inscribed in the National Civil Register, by presenting a detailedproposal which shall be referred to the President of the General Assembly, tobe submitted for popular decision at the next election.
The General Assembly, meeting in jointsession, may take substitute proposals which shall be submitted to plebiscitarydecision together with the popular initiative.