Dealing with legacy systems has been a challenge for the industry for decades. The pressure to efficiently modernise legacy assets to meet new business needs and minimise associated risks is increasing. Automated code transformation, which is associated with serious (long-known) risks, is a high priority in the industrial environment due to the cost structure, the effort required and the supposed time savings. However, little has been published about the long-term effects of successful migrations. This paper looks at three different cases of automated code transformation at different stages of their lifecycle, highlights the lessons learned and derives a number of recommendations that should be useful for planning and executing future transformations.