Every site that depends on a mainframe is at a slightly different stage in dealing with the retiring work force. All of these sites would agree that the layout of their mainframe staff in the future may bear little resemblance to the way it looks today.
Meet your mainframe staff, 2020:
Your systems programmer came in with a liberal arts degree but impressed everyone with her natural curiosity and intelligence during the interview process. Once on board she apprenticed to your most senior systems staff. And when her mentors retired, she was ready, willing and able to perform all necessary systems programming tasks up to and including overseeing your outsourced systems staff to ensure the timeliness and accuracy of their output.
Your application developer came in with a Computer Science degree and was already well steeped in Linux, both scholastically and recreationally. This enabled him to quickly adapt to zLinux. And although he hates both TSO and ISPF, he is adept at using your modernized mainframe tooling to make any necessary adjustments to your back end legacy applications. His well-rounded background gives him an added advantage when working with your complex Web driven applications.
Your QA analyst was a music major. The attention to detail learned in that study has served him well when identifying subtle bugs in your complex applications. His ability to improvise has allowed him to develop effective techniques to test your multi-tier Web applications. His appreciation of your taking a chance on him makes him a loyal, engaged employee.
Your concern over the retiring mainframe work force is still omni-present but no longer dominates your day-to-day decision making. You are confident that smart motivated people, where ever you find them, make great employees.