Needed to replace a nullable column in a database with a non nullable column that.  In this case a boolean field needed to transition so came up with this to alter the structure it.  The following statement does not transition the contents of the original column to the new column.  For me this is acceptable as the application code was written to be idempotent and would reload the appropriate data as soon as it is called again (this was achieved with a explicit matching set of fields and a merge statement)

USE [target_db];
ALTER TABLE [dbo].[target_table] ADD [column_to_add] [bit] NOT NULL CONSTRAINT [DF_target_table_column_to_add]  DEFAULT 0;
ALTER TABLE [dbo].[target_table] DROP COLUMN [column_to_replace]