What specific dates are mentioned in the context related to the India-Bangladesh agreement and its protocol?
The specific dates mentioned in the context related to the India-Bangladesh agreement and its protocol are: 16th day of May, 1974 (agreement), 26th day of December, 1974 (Exchange of Letters), the 30th day of December, 1974 (Exchange of Letters), the 7th day of October, 1982 (Exchange of Letters), the 26th day of March, 1992 (Exchange of Letters), and the 6th day of September, 2011 (protocol).