By implementing new technologies, enterprise architectures and their respective models are subject to change. Current changes of the enterprise architecture are often driven by the IT megatrends. In this paper, we analyze six explorative projects from a logistics company that implemented Internet of Things (IoT) technology. Our analysis focusses on a cross-case comparison of the project specific enterprise architecture (EA) models based on an integrated model. The models and its meta-model were developed in an action design research based project. The results show that in-depth insights into IoT projects and a unified way of modelling support the process of analyzing the current architecture and deriving recommendations for the to-be architecture. Furthermore, we identify and discuss five IoT-specific EA challenges for future integration and roll-out projects and provide preliminary suggestions for overcoming them.