It would be logical for verses 17-19 to follow directly after verse 14. What is described here could either refer to the continuing contacts with Tobiah after the completion of the wall or it could be a summary statement referring to the general situation before the completion of the wall.
Moreover in those days can refer to the period of time that has been under discussion, as in Neh 13.23, rather than being a marker for a new, subsequent event. In this case it could be translated “During all this time” (Good News Translation), “Even in those days,” “Throughout that period,” or “All this time” (New English Bible).
For nobles see Neh 2.16.
Sent many letters … letters came: See the comments on verse 5 above. Communication went back and forth. New English Bible speaks of “sending many letters” and “receiving replies.” Good News Translation therefore refers to it as “correspondence” and Bible en français courant says “much correspondence.” Translators should use a verb pattern that represents continual or repeated action.
Quoted with permission from Noss, Philip A. and Thomas, Kenneth J. A Handbook on Nehemiah. (UBS Helps for Translators). New York: UBS, 2005. For this and other handbooks for translators see here .