The subject matter of a meeting or the determination to open or close a
meeting or a portion of a meeting to public observation may be changed
following public announcement under section 261b.6 only if a majority of the
members of the agency determines by a recorded vote that agency business so
requires and that no earlier announcement of the change was possible. Public
announcement of such change and the vote of each member upon such change will
be made pursuant to section 261b.6(c). Changes in time, including
postponements and cancellations of a publicly announced meeting or portion of
a meeting or changes in the place of a publicly announced meeting will be
publicly announced pursuant to section 261b.6(c) by the secretary of the
Board or, in the secretary’s absence, the acting secretary of the
Board.