Abstract
With the inception of the web now being more than 20 years ago, many web-based learning technology systems (LTS) have had a long life and have undergone many changes, both affecting content and infrastructure technologies. A change factor model can capture the various factors causing LTS to change. Methods for change-aware design of LTS have been suggested. The purpose of this investigation is, firstly, to add empirical results to aspects of these models and methods in order to show the relevance of such a change factor model by specifically looking at an LTS that has been developed, maintained and extended over a period of 20 years. Secondly, these results shall be used to develop a conceptual model capturing and assessing the impact of change. A key observation is an unexpectedly high impact of environmental constraints on the LTS, but also new opportunities emerging over time have had dramatic changes as their consequence.