Dietrich Leads NBT Bancorp; Watt To Succeed Him In 2017 NORWICH – 2016 will be a year of change in NBT Bancorp’s executive offices, the company announced after its board of directors approved a succession plan Tuesday. NBT Bancorp President/CEO Martin A. Dietrich was promoted to chairman on Tuesday, following the retirement of Daryl R. Forsythe, but only until the end of this year. At that point, Dietrich will retire and by succeeded by John H. Watt Jr., who Tuesday…