As is laid out in each Chapter's By-laws, all Chapters are required to have a Board, elected in the way described in the By-laws. Terms and positions are also outlined in the By-laws. Things like term limits, and other details about the Board or elections, may go into a policy manual, if you choose to create one. The lack of a detailed By-laws description of things like term limits, rejoining the Board in another role, etc., gives Chapters leeway to abide by their By-laws, but execute a process/election that can be tailored to their needs.
You can review the ACBS Chapter Board Handbook for more detailed information here.