Darnell, who served on the board since 1992, will be honored at a funeral Monday.
On Wednesday, Fulton County commissioners will decide on the suggested Sept. 17 election date, with an Oct. 15 runoff, if necessary.
If commissioners approve the special election date, qualifying will take place June 24-28. The term runs through the end of 2020.
Darnell represented parts of south Fulton County.
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