We performed a retrospective meeting at a case company to reflect on its decade of Software Process Improvement (SPI) activities for enhancing UX integration. We supported the meeting by a pre-generated timeline of the main activities. This approach is a refinement of a similar approach that is used in Agile projects to improve effectiveness and decrease memory bias of retrospective meetings. The method is evaluated through gathering practitioners' view using a questionnaire. We conclude that UX research and practice can benefit from the SPI body of knowledge. We also argue that a cross-section evidence-based timeline retrospective meeting is useful for enhancing UX work in companies, especially for identifying and reflecting on `organizational issues'. This approach also provides a cross-section longitudinal overview of the SPI activities that cannot easily be gained in other common SPI learning approaches.