The migration of code and JCL is a very streight forward process. When COBOL is your code base the changes are minimal, this is one of the advantages of COBOL usage, it is all standardized. However, vendor specific extentions are the challenge. We aim to leave the code as much as possible "as is" and re-route specific calls to external library entries providing similar funtionality. Syntax and semantical differences will be amended in the migrated sources.
JCL will be replaced by PowerShell scripting in a job control runtime environment.
The resulting code is guaranteed to be just as maintainable as it was before the migration. In some respects even better!