See this thread, which has fundamentally the same answer.  (There, the user is trying to change the Preparer/Staff Preparer fields.  You want to make similar changes, just to different fields.)
  https://proconnect.intuit.com/community/lacerte-tax-discussions/discussion/mass-reassignment-of-prep...

Including specifically where I link to the articles where the SDK is available.  Create your ODBC connection, and then use your software of choice to look at the table of client data and fill in what you need to.

If you already have that information somewhere else (like in your CRM software), you can use a script or macro to say "find this client #, if <this field, like "salutation"> is blank then fill in <this value, from source data>."



Robert Kirk
LTUGtools