I used this approach to migrate our business-critical database from SQL Server 2008 to SQL Server 2016 while changing the data type of primary key column having deep penetration in the database itself ...

With Extended Support for SQL Server 2008 and SQL Server 2008 R2 ending in July 2019, to be followed six months later by the end of Extended Support for Windows Server 2008 and 2008 R2 in January 2020 ...