The European XFEL has started User Operation in 2017 and since 2022 is considered to be fully operational. The facility is now run for User Experiments and is creating a lot of scientific results. It is expected that this Harvesting phase will last well into the 2030 years, before an extension or upgrade of the facility or parts thereof will be needed to respond to the increased and developed scientific request by its User Communities.
Upgrade options concern the electron accelerator, the FEL sources, the scientific instruments, but as well instrumentation required for the experiments. Responding to the request for more User Experiments and for scientific instrument optimized for specific applications will be possible by extending the number of FELs and scientific instruments. In addition, it has to be considered that parts of the facility require refurbishment after approx. 20 years of operation.
