Where bonds are issued by any school district under the provisions of Section 19-2 through Section 19-6, and before any contract is let for the construction of buildings or improvements in accordance therewith the district boundaries are changed by the formation of a new district including all or a part of said district, or by the annexation of a district in its entirety to another district, then upon the adoption of a resolution by the board of education of the new district or the district to which the territory has been annexed, that the building or improvements are no longer feasible, the board shall by resolution order submitted to the electors the proposition of authorizing the board to use the proceeds of said bonds or the portion thereof allotted to the new district or district to which said territory is annexed for a specific new building or improvement in some locality of the district other than the one specified at the previous election, or for a different improvement, or for a part of the original improvements. In case a new district has been formed, no such referendum shall be held unless the new district embraces territory having as much or more assessed valuation as the territory embraced in the district at the first election. The board shall certify the resolution and the proposition to the proper election authorities for submission in accordance with the general election law.
     Where bonds are issued by any school district under the provisions of Section 19-2 through Section 19-6, and it is determined by the board of education by resolution that it is in the interests of the school district that part or all of the proceeds of said bonds be used for different purposes than authorized but for purposes for which bonds may be issued under the provisions of Section 19-2 through Section 19-6, the board shall by resolution order submitted to the electors the proposition of authorizing the board to use the proceeds of said bonds or a part thereof for the purposes set forth in said resolution and if a majority of all the votes cast on said proposition is in favor thereof the board shall have such authority. The board shall certify the resolution and the proposition to the proper election authorities for submission in accordance with the general election law.