The initial members of the council and the new members required by the changes to section 25-2905 made by Laws 2019, LB595, shall be appointed for terms of one, two, or three years. All subsequent appointments shall be made for terms of three years. Any vacancy on the council shall be filled and shall last for the duration of the term vacated. Appointments to the council required by changes to section 25-2905 made by Laws 2019, LB595, shall be made within ninety days after September 1, 2019. The council shall select a chairperson, a vice-chairperson, and such other officers as it deems necessary.