Bill
How about starting a list of dispatcher offices with some known employee timetable or dispatcher sheets dates and then we can modify the years for those that have earlier and later employee timetables or train sheets.

Eastern Division
September 1900
St. Louis, Mo for St. Louis to Chamois, Missouri section
January 1939 – March 1942
Cole Junction, Mo (later named Cole, Mo) and Pacific, Missouri (K Tower) dispatchers still at Pacific in February 1961
September 1963 – July 1964
Jefferson City, Mo
Open question is when were the dispatchers moved to Jefferson City from Cole and Pacific?

White River Division –
December 1932
Aurora, Missouri
Nevada, Missouri
October 1936 to August 1948
Nevada, Missouri
1906-1933 (source Mike Adams White River Division book)
Cotter, Arkansas

Omaha-Northern Kansas Division
March 1943 – February 1959
Atchison, Kansas

Kingsville Division
January 1931 – January 1943
Kingsville, Texas

Palestine Division
October 1931 – September 1950
Palestine, Texas

Missouri Division
September 1935 – February 1943
Poplar Bluff, Missouri

Arkansas Division
April 1932 – May 1961
Little Rock, Arkansas
May 1961
Gurdon, Arkansas

Central Kansas and Colorado Divisions
February 1943
Osawatomie, Kansas
Pueblo, Colorado

San Antonio Division
October 1931
San Antonio, Texas
August 1943 –
San Antonio, Tx and Palestine, Tx
January 1956
Not shown in timetable

Gulf Coast Lines Goose Creek Subdivision
July 1943
Houston, Texas

Gulf Coast Lines DeQuincy Division
July 1921 – July 1931
DeQuency, La

Illinois Division
August 1933 – May 1943
Bush, Illinois

Memphis division
February 1943
Wynne, Arkansas

Missouri-Illinois RR
Bush, Illinois April 1932
Bonne Terre, Missouri July 1944 – January 1957

Wichita Division
March 1943
Wichita, Kansas

Southern Kansas
June 1927 – June 1944
Coffeyville, Kansas

San Antonio, Uvalde & Gulf
October 1925
North Pleasanton, Texas