A motion to amend an amendment shall be in order, but one to amend an amendment to an amendment shall not be entertained.
An amendment modifying the intention of a motion shall be in order, but an amendment relating to a different subject shall not be in order.
On an amendment to "strike out and insert" the paragraph to be amended shall first be read as it stands, then the words proposed to be stricken out and those to be inserted and, finally, the paragraph as it will stand if so amended shall be read.
A substitute for any original proposition in debate may be entertained when further amendment is not admissible; but if accepted by the mover of such original proposition, or by the board by vote, it shall entirely supersede the original proposition and cut off all amendments appertaining thereto. (1965 Code)