This isn't as radical as it sounds. Experienced managers with related qualifications could be hired on a contract basis through third party vendors to lead individual or system-wide projects. When the project is complete they can be retrenched.
Given the high turnover and attrition among directly hired junior managers, this could significantly reduce training/labor costs and plug the experience gaps between agreement and non-agreement employees. This can be done while retaining senior craft employees as a professional corps for their skills and knowledge.
The way the workforce reduction has been implemented is the direct opposite: continually hire new and inexperienced managers directly while cutting the craft people with skills that are essential to making the railroad work.